[Doc] doc of pg generated as identity-docs-AtomGit

Mdocs-lite/zh/database_reference/PG_ATTRIBUTE.md+14-0

	@@ -190,5 +190,19 @@ PG\_ATTRIBUTE系统表存储关于表字段的信息。
190	<p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a>3. ATT_KV_TIMETAG :时间列</p>	190	<p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a>3. ATT_KV_TIMETAG :时间列</p>
191	</td>	191	</td>
192	</tr>	192	</tr>
		193	+<tr id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_row1718431494418"><td class="cellrowborder" valign="top" width="14.499999999999998%" headers="mcps1.2.4.1.1 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a>attdroppedname</p>
		194	+</td>
		195	+<td class="cellrowborder" valign="top" width="17.919999999999998%" headers="mcps1.2.4.1.2 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a>name</p>
		196	+</td>
		197	+<td class="cellrowborder" valign="top" width="67.58%" headers="mcps1.2.4.1.3 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a>被删除前的字段名</p>
		198	+</td>
		199	+</tr>
		200	+<tr id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_row1718431494418"><td class="cellrowborder" valign="top" width="14.499999999999998%" headers="mcps1.2.4.1.1 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a>attidentity</p>
		201	+</td>
		202	+<td class="cellrowborder" valign="top" width="17.919999999999998%" headers="mcps1.2.4.1.2 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a>char</p>
		203	+</td>
		204	+<td class="cellrowborder" valign="top" width="67.58%" headers="mcps1.2.4.1.3 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a>某一列的identity属性, 取值为'a','d'或者'm'</p>
		205	+</td>
		206	+</tr>
193	</tbody>	207	</tbody>
194	</table>	208	</table>

Mdocs-lite/zh/extension_reference/shark-ALTER-TABLE.md+66-23

	@@ -30,6 +30,7 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
30		30
31	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。	31	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。
32	- filegroup为任意字符串，支持通过[]包裹。	32	- filegroup为任意字符串，支持通过[]包裹。
		33	+- 新增支持为列添加identity属性的语法。
33		34
34	## 语法格式<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s58bdce220c9f4292ba9af919b04ad25c"></a>	35	## 语法格式<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s58bdce220c9f4292ba9af919b04ad25c"></a>
35		36
	@@ -89,21 +90,23 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
89		90
90	```	91	```
91	[ CONSTRAINT constraint_name ]	92	[ CONSTRAINT constraint_name ]
92	- { NOT NULL \|	93	+ { NOT NULL \|
93	- NULL \|	94	+ NULL \|
94	- CHECK ( expression ) \|	95	+ CHECK ( expression ) \|
95	- DEFAULT default_expr \|	96	+ DEFAULT default_expr \|
96	- GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	97	+ IDENTITY [ ( seed, increment ) ] \|
97	- AUTO_INCREMENT \|	98	+ GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
98	- ON UPDATE update_expr \|	99	+ ON UPDATE update_expr \|
99	- UNIQUE [KEY] index_parameters [ ON filegroup ] \|	100	+ { UNIQUE [KEY] index_parameters [ ON filegroup ] \|
100	- PRIMARY KEY index_parameters [ ON filegroup ] \|	101	+ PRIMARY KEY index_parameters [ ON filegroup ]
101	- ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|	102	+ } [ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] \|
102	- REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]	103	+ REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]
103	- [ ON DELETE action ] [ ON UPDATE action ] }	104	+ [ ON DELETE action ] [ ON UPDATE action ] [ ENABLE ] \|
104	- [ ENABLE [VALIDATE \| NOVALIDATE] \| DISABLE [VALIDATE \| NOVALIDATE] ]	105	+ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] Constraint constraint_name \|
105	- [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|	106	+ DEFAULT (expression) FOR (column_name) } \|
106	- DEFAULT (expression) FOR (column_name)	107	+ AUTO_INCREMENT \|
		108	+ ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|
		109	+ [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|
107	[ COMMENT 'text' ]	110	[ COMMENT 'text' ]
108	```	111	```
109		112
	@@ -211,22 +214,27 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
211	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。	214	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。
212	- filegroup为任意字符串，支持通过[]包裹。	215	- filegroup为任意字符串，支持通过[]包裹。
213		216
214	-- DEFAULT (expression) FOR (column_name)	217	+- DEFAULT \( expression \) FOR \( column\_name \)
215		218
216	- 该语法可以为指定列添加DEFAULT约束，该约束为一个表达式。	219	- 该语法可以为指定列添加DEFAULT约束，该约束为一个表达式。
217	- 对于显式声明约束名的场景，仅做语法支持，使用该语法创建的DEFAULT约束无法通过约束名进行删除。	220	- 对于显式声明约束名的场景，仅做语法支持，使用该语法创建的DEFAULT约束无法通过约束名进行删除。
218		221
219	-## opt\_clustered示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	222	+- IDENTITY \[ ( seed, increment ) \]
220		223
221	-```	224	+ - 该语法为列添加identity属性，序列值递增，`seed`指定起始值，`increment`指定步长。
		225	+ - 一张表只能定义一列（包括generated as identity）。
		226	+
		227	+## opt\_clustered示例
		228	+
		229	+```sql
222	openGauss=# CREATE TABLE alter_table_tbl1 (a INT, b INT);	230	openGauss=# CREATE TABLE alter_table_tbl1 (a INT, b INT);
223	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_a UNIQUE CLUSTERED (a);	231	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_a UNIQUE CLUSTERED (a);
224	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_b PRIMARY KEY NONCLUSTERED (a);	232	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_b PRIMARY KEY NONCLUSTERED (a);
225	```	233	```
226		234
227	-## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	235	+## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例
228		236
229	-```	237	+```sql
230	create table test1(col1 int primary key with(fillfactor = 20), col2 int);	238	create table test1(col1 int primary key with(fillfactor = 20), col2 int);
231	NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test1_pkey" for table "test1"	239	NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test1_pkey" for table "test1"
232		240
	@@ -251,9 +259,9 @@ NOTICE: parameter "data_compression" is currently ignored.
251	NOTICE: ALTER TABLE / ADD PRIMARY KEY will create implicit index "test3_pkey" for table "test3"	259	NOTICE: ALTER TABLE / ADD PRIMARY KEY will create implicit index "test3_pkey" for table "test3"
252	```	260	```
253		261
254	-## filegroup示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	262	+## filegroup示例
255		263
256	-```	264	+```sql
257	create table test1(col1 int primary key with(fillfactor = 20), col2 int);	265	create table test1(col1 int primary key with(fillfactor = 20), col2 int);
258		266
259	alter table test1 add constraint unique_name unique(col2) with (fillfactor = 50, ignore_dup_key = on) on [primary1];	267	alter table test1 add constraint unique_name unique(col2) with (fillfactor = 50, ignore_dup_key = on) on [primary1];
	@@ -269,9 +277,44 @@ create table test3(col1 int, col2 int);
269	alter table test3 add column col3 int primary key with (data_compression = none) on [primar4];	277	alter table test3 add column col3 int primary key with (data_compression = none) on [primar4];
270	```	278	```
271		279
272	-## DEFAULT (expression) FOR (column_name) 示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	280	+## IDENTITY \[ \( seed, increment \) \] 示例
		281	+```sql
		282	+openGauss=# create extension shark;
		283	+CREATE EXTENSION
		284	+openGauss=# create table t1 (a int identity(10, 20), b int);
		285	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq_identity" for serial column "t1.a"
		286	+CREATE TABLE
		287	+openGauss=# \d+ t1
		288	+ Table "public.t1"
		289	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		290	+--------+---------+-------------------+---------+--------------+-------------
		291	+ a \| integer \| not null identity \| plain \| \|
		292	+ b \| integer \| \| plain \| \|
		293	+Has OIDs: no
		294	+Options: orientation=row, compression=no, collate=1537
		295	+Character Set: UTF8
		296	+Collate: utf8mb4_general_ci
		297	+
		298	+openGauss=# alter table t1 alter column b add identity ;
		299	+NOTICE: ALTER TABLE will create implicit sequence "t1_b_seq_identity" for serial column "t1.b"
		300	+ERROR: Multiple identity columns specified for table "t1". Only one identity column per table is allowed.
		301	+openGauss=# create table t2 (a int, b int);
		302	+CREATE TABLE
		303	+openGauss=# alter table t2 alter column b add identity ;
		304	+NOTICE: ALTER TABLE will create implicit sequence "t2_b_seq_identity" for serial column "t2.b"
		305	+ERROR: column "b" of relation "t2" must be declared NOT NULL before identity can be added
		306	+openGauss=# alter table t2 alter column b set not null;
		307	+ALTER TABLE
		308	+openGauss=# alter table t2 alter column b add identity ;
		309	+NOTICE: ALTER TABLE will create implicit sequence "t2_b_seq_identity" for serial column "t2.b"
		310	+ALTER TABLE
		311	+openGauss=#
273		312
274	```	313	```
		314	+
		315	+## DEFAULT (expression) FOR (column_name) 示例
		316	+
		317	+```sql
275	openGauss=# create table ADD_DEFAULT(id int, v1 varchar(20), v2 float);	318	openGauss=# create table ADD_DEFAULT(id int, v1 varchar(20), v2 float);
276	CREATE TABLE	319	CREATE TABLE
277	openGauss=# \d+ ADD_DEFAULT	320	openGauss=# \d+ ADD_DEFAULT

Mdocs-lite/zh/extension_reference/shark-CREATE-TABLE.md+42-2

	@@ -64,6 +64,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
64	NULL \|	64	NULL \|
65	CHECK ( expression ) \|	65	CHECK ( expression ) \|
66	DEFAULT default_expr \|	66	DEFAULT default_expr \|
		67	+ IDENTITY [ ( seed, increment ) ] \|
67	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	68	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
68	AS ( generation_expr ) [PERSISTED] \|	69	AS ( generation_expr ) [PERSISTED] \|
69	AUTO_INCREMENT \|	70	AUTO_INCREMENT \|
	@@ -101,6 +102,11 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
101		102
102	## 参数说明	103	## 参数说明
103		104
		105	+- IDENTITY \[ \( seed, increment \) \]
		106	+
		107	+ - 该语法为列添加identity属性，序列值递增，`seed`指定起始值，`increment`指定步长。
		108	+ - 一张表只能定义一列（包括generated as identity）。
		109	+
104	- AS \( generation\_expr \) \[PERSISTED\]	110	- AS \( generation\_expr \) \[PERSISTED\]
105		111
106	该子句为兼容D库的语法，将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，PERSISTED表示像普通列一样存储生成列的值。	112	该子句为兼容D库的语法，将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，PERSISTED表示像普通列一样存储生成列的值。
	@@ -234,6 +240,40 @@ opengauss=# ALTER TABLE Products DROP unitprice;
234	ALTER TABLE	240	ALTER TABLE
235	```	241	```
236		242
		243	+## IDENTITY \[ \( seed, increment \) \] 示例
		244	+```sql
		245	+openGauss=# create extension shark;
		246	+CREATE EXTENSION
		247	+openGauss=# create table t1 (a int identity(10, 20), b int);
		248	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq_identity" for serial column "t1.a"
		249	+CREATE TABLE
		250	+openGauss=# \d+ t1
		251	+ Table "public.t1"
		252	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		253	+--------+---------+-------------------+---------+--------------+-------------
		254	+ a \| integer \| not null identity \| plain \| \|
		255	+ b \| integer \| \| plain \| \|
		256	+Has OIDs: no
		257	+Options: orientation=row, compression=no, collate=1537
		258	+Character Set: UTF8
		259	+Collate: utf8mb4_general_ci
		260	+
		261	+openGauss=# insert into t1(b) values(10);
		262	+INSERT 0 1
		263	+openGauss=# insert into t1(a, b) overriding system value values(12, 10);
		264	+INSERT 0 1
		265	+openGauss=# insert into t1 default values;
		266	+INSERT 0 1
		267	+openGauss=# select * from t1;
		268	+ a \| b
		269	+----+----
		270	+ 10 \| 10
		271	+ 12 \| 10
		272	+ 30 \|
		273	+(3 rows)
		274	+
		275	+```
		276	+
237	## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例	277	## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例
238		278
239	```sql	279	```sql
	@@ -326,7 +366,7 @@ openGauss=# CREATE TEMPORARY TABLE #ltt1
326	ADDRESS VARCHAR(50) ,	366	ADDRESS VARCHAR(50) ,
327	POSTCODE CHAR(6)	367	POSTCODE CHAR(6)
328	) ON COMMIT PRESERVE ROWS;	368	) ON COMMIT PRESERVE ROWS;
329	-	369	+CREATE TABLE
330	openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1	370	openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1
331	(	371	(
332	ID INTEGER NOT NULL,	372	ID INTEGER NOT NULL,
	@@ -334,7 +374,7 @@ openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1
334	ADDRESS VARCHAR(50) ,	374	ADDRESS VARCHAR(50) ,
335	POSTCODE CHAR(6)	375	POSTCODE CHAR(6)
336	) ON COMMIT PRESERVE ROWS;	376	) ON COMMIT PRESERVE ROWS;
337	-	377	+CREATE TABLE
338	```	378	```
339		379
340	## 相关链接<a name="section156744489391"></a>	380	## 相关链接<a name="section156744489391"></a>

Mdocs-lite/zh/extension_reference/shark-INSERT.md+66-2

 ```
 [ WITH [ RECURSIVE ] with_query [, ...] ]
 INSERT [/*+ plan_hint */] [INTO] table_name [partition_clause] [ AS alias ] [table_hint_clause] [ ( column_name [, ...] ) ]
++    [ OVERRIDING { SYSTEM | USER } VALUE ]
     { DEFAULT VALUES
     | VALUES {( { expression | DEFAULT } [, ...] ) }[, ...]
     | query }
     - 针对hint，会打印相关NOTICE信息。
++- **OVERRIDING \{ SYSTEM | USER \} VALUE**
++    该子句用于插入identity列时的行为控制。
++
++    - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
++    - 当开启`identity_insert`时可以插入用户值（包括default），否则只有使用`OVERRIDING SYSTEM VALUE`才能插入用户值，而insert overriding user value会忽略用户的值采用序列的值。
++
++## table_hint子句示例
++
++```sql
 create table t1(c1 int, c2 int);
 insert into t1 values(1, 2);
 NOTICE:  The nowait option is currently ignored
 ```
++## identity_insert 与 OVERRIDING clause 示例
++```sql
++openGauss=# create extension shark;
++CREATE EXTENSION
++openGauss=#  CREATE TABLE book(bookId int IDENTITY, bookname NVARCHAR(50), author NVARCHAR(50));
++NOTICE:  CREATE TABLE will create implicit sequence "book_bookid_seq_identity" for serial column "book.bookid"
++CREATE TABLE
++openGauss=# \d+ book
++                                               Table "public.book"
++  Column  |     Type      |                   Modifiers                   | Storage  | Stats target | Description
++----------+---------------+-----------------------------------------------+----------+--------------+-------------
++ bookid   | integer       | not null identity                             | plain    |              |
++ bookname | nvarchar2(50) | character set UTF8 collate utf8mb4_general_ci | extended |              |
++ author   | nvarchar2(50) | character set UTF8 collate utf8mb4_general_ci | extended |              |
++Has OIDs: no
++Options: orientation=row, compression=no, collate=1537
++Character Set: UTF8
++Collate: utf8mb4_general_ci
++
++openGauss=# set identity_insert = off;
++SET
++openGauss=# INSERT INTO book VALUES (2, 'xxx', 'xxx'); -- error;
++ERROR:  INSERT has more expressions than target columns
++LINE 1: INSERT INTO book VALUES (2, 'xxx', 'xxx');
++                                           ^
++openGauss=# INSERT INTO book (bookid, bookname, author) VALUES(11111, 'xxxx', 'xxx'); -- error, turn on identity_insert or use OVERRIDING
++ERROR:  cannot insert a non-DEFAULT value into column "bookid"
++DETAIL:  Column "bookid" is an identity column defined as "IDENTITY".
++HINT:  Use OVERRIDING SYSTEM VALUE to override, Or turn on "identity_insert".
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING SYSTEM VALUE VALUES (33, 'xxx', 'xxx'); -- success; -- 33
++INSERT 0 1
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING USER VALUE VALUES (11111, 'xxx', 'xxx'); -- success; -- 1
++INSERT 0 1
++openGauss=# set identity_insert = on;
++SET
++openGauss=# INSERT INTO book VALUES (44, 'xxx', 'xxx'); -- error;
++ERROR:  INSERT has more expressions than target columns
++LINE 1: INSERT INTO book VALUES (44, 'xxx', 'xxx');
++                                            ^
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING USER VALUE VALUES (11111, 'xxx', 'xxx'); -- success; -- 2
++INSERT 0 1
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING SYSTEM VALUE VALUES (55, 'xxx', 'xxx'); -- success; -- 55
++INSERT 0 1
++openGauss=# set identity_insert = off;
++SET
++openGauss=# select * from book order by 1, 2;
++ bookid | bookname | author
++--------+----------+--------
++      1 | xxx      | xxx
++      2 | xxx      | xxx
++     33 | xxx      | xxx
++     55 | xxx      | xxx
++(4 rows)
++
++```
++
 ## 相关链接<a name="section156744489391"></a>
 [INSERT](../sql_reference/INSERT.md)

Mdocs-lite/zh/extension_reference/shark-MERGE-INTO.md+61-3

	@@ -24,8 +24,9 @@ ON ( condition )
24	]	24	]
25	[	25	[
26	WHEN NOT MATCHED THEN	26	WHEN NOT MATCHED THEN
27	- INSERT { DEFAULT VALUES \|	27	+ INSERT [ ( column_name [, ...] ) ]
28	- [ ( column_name [, ...] ) ] VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }	28	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
		29	+ { DEFAULT VALUES \| VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }
29	];	30	];
30	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!	31	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!
31	```	32	```
	@@ -50,9 +51,17 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
50		51
51	- 针对hint，会打印相关NOTICE信息。	52	- 针对hint，会打印相关NOTICE信息。
52		53
		54	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		55	+
		56	+ 该子句用于插入identity列时的行为控制。
		57	+
		58	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		59	+ - 当开启`identity_insert`时可以插入用户值（包括default），否则只有使用`OVERRIDING SYSTEM VALUE`才能插入用户值，而insert overriding user value会忽略用户的值采用序列的值。
		60	+
53	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>	61	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>
54		62
55	-```	63	+- merge into语句基础示例
		64	+```sql
56	-- 创建目标表products和源表newproducts，并插入数据	65	-- 创建目标表products和源表newproducts，并插入数据
57	openGauss=# CREATE TABLE products	66	openGauss=# CREATE TABLE products
58	(	67	(
	@@ -154,6 +163,55 @@ openGauss=# DROP TABLE products;
154	openGauss=# DROP TABLE newproducts;	163	openGauss=# DROP TABLE newproducts;
155	```	164	```
156		165
		166	+- identity_insert 与 OVERRIDING clause 示例
		167	+```sql
		168	+openGauss=# create table target_table ( id int identity, name varhcar(50), age int);
		169	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq_identity" for serial column "target_table.id"
		170	+ERROR: type "varhcar" does not exist
		171	+LINE 1: create table target_table ( id int identity, name varhcar(50...
		172	+ ^
		173	+openGauss=# create table target_table ( id int identity, name varchar(50), age int);
		174	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq_identity" for serial column "target_table.id"
		175	+CREATE TABLE
		176	+openGauss=# create table source_table (id int, name varchar(50), age int);
		177	+CREATE TABLE
		178	+openGauss=# insert into source_table values (10, 'zliu', 28), (11, 'sqi', 30);
		179	+INSERT 0 2
		180	+openGauss=# set identity_insert = off;
		181	+SET
		182	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		183	+openGauss-# when not matched then
		184	+openGauss-# insert (name, age) values (s.name, s.age);
		185	+MERGE 2
		186	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		187	+openGauss-# when not matched then
		188	+openGauss-# insert (id, name, age) values (1, 'error', 21);
		189	+ERROR: cannot insert a non-DEFAULT value into column "id"
		190	+DETAIL: Column "id" is an identity column defined as "IDENTITY".
		191	+HINT: Use OVERRIDING SYSTEM VALUE to override, Or turn on "identity_insert"
		192	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		193	+openGauss-# when not matched then
		194	+openGauss-# insert (id, name, age) OVERRIDING USER VALUE values (1, 'success', 22); -- 3
		195	+MERGE 2
		196	+openGauss=# set identity_insert = on;
		197	+SET
		198	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		199	+openGauss-# when not matched then
		200	+openGauss-# insert (id, name, age) values (s.id + 2, 'success', s.age);
		201	+MERGE 2
		202	+openGauss=# select * from target_table order by 1, 2,3;
		203	+ id \| name \| age
		204	+----+---------+-----
		205	+ 1 \| zliu \| 28
		206	+ 2 \| sqi \| 30
		207	+ 3 \| success \| 22
		208	+ 4 \| success \| 22
		209	+ 12 \| success \| 28
		210	+ 13 \| success \| 30
		211	+(6 rows)
		212	+
		213	+```
		214	+
157	## 相关链接<a name="section156744489391"></a>	215	## 相关链接<a name="section156744489391"></a>
158		216
159	[MERGE INTO](../sql_reference/merge_into.md)	217	[MERGE INTO](../sql_reference/merge_into.md)

Mdocs-lite/zh/sql_reference/INSERT.md+32-0

	@@ -30,6 +30,7 @@
30	INSERT [/+ plan_hint /] INTO	30	INSERT [/+ plan_hint /] INTO
31	{ table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]	31	{ table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]
32	\| ( target_query [ WITH [ CASCADED \| LOCAL ] CHECK OPTION ] ) [ AS ] alias [ ( column_name [, ...] ) ] }	32	\| ( target_query [ WITH [ CASCADED \| LOCAL ] CHECK OPTION ] ) [ AS ] alias [ ( column_name [, ...] ) ] }
		33	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
33	{ DEFAULT VALUES	34	{ DEFAULT VALUES
34	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]	35	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]
		ywzq11613277847月29日【问题描述】 docs-lite/zh/sql_reference/INSERT.md docs-lite/zh/sql_reference/REPLACE_INTO.md 【修改建议】这俩文件非lite版本也添加下，保证lite版本和非lite版本保持一致 XXXCA 7月29日评论： 7月29日评论：
35	\| query }	36	\| query }
	@@ -111,6 +112,12 @@ INSERT [/+ plan_hint /] INTO
111		112
112	取值范围：已存在的字段名。	113	取值范围：已存在的字段名。
113		114
		115	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		116	+
		117	+ 该子句用于插入identity列时的行为控制。
		118	+
		119	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		120	+
114	- expression	121	- expression
115		122
116	赋予对应column的一个有效表达式或值：	123	赋予对应column的一个有效表达式或值：
	@@ -251,6 +258,8 @@ INSERT [/+ plan_hint /] INTO
251		258
252	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>	259	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>
253		260
		261	+- insert语句基础示例
		262	+
254	```sql	263	```sql
255	--创建表tpcds.reason_t2。	264	--创建表tpcds.reason_t2。
256	openGauss=# CREATE TABLE tpcds.reason_t2	265	openGauss=# CREATE TABLE tpcds.reason_t2
	@@ -410,3 +419,26 @@ UPDATE SET email = EXCLUDED.email;
410	INSERT INTO users (id, email, name)	419	INSERT INTO users (id, email, name)
411	VALUES (7, 'frank@example.com', 'Frank') ON CONFLICT (email text_pattern_ops) DO NOTHING;	420	VALUES (7, 'frank@example.com', 'Frank') ON CONFLICT (email text_pattern_ops) DO NOTHING;
412	```	421	```
		422	+
		423	+- OVERRIDING 子句示例
		424	+```sql
		425	+openGauss=# create table t1 (a int generated always as identity, b int);
		426	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq" for serial column "t1.a"
		427	+CREATE TABLE
		428	+openGauss=# insert into t1(a, b) values(1, 1);
		429	+ERROR: cannot insert a non-DEFAULT value into column "a"
		430	+DETAIL: Column "a" is an identity column defined as "GENERATED ALWAYS".
		431	+HINT: Use OVERRIDING SYSTEM VALUE to override.
		432	+openGauss=# insert into t1(a, b) OVERRIDING SYSTEM VALUE values(10, 1);
		433	+INSERT 0 1
		434	+openGauss=# insert into t1(a, b) OVERRIDING USER VALUE values(10, 1);
		435	+INSERT 0 1
		436	+openGauss=# select * from t1 order by a, b;
		437	+ a \| b
		438	+----+---
		439	+ 1 \| 1
		440	+ 2 \| 1
		441	+ 10 \| 1
		442	+(3 rows)
		443	+
		444	+```

Mdocs-lite/zh/sql_reference/REPLACE_INTO.md+25-1

	@@ -16,6 +16,7 @@
16	```	16	```
17	[ WITH [ RECURSIVE ] with_query [, ...] ]	17	[ WITH [ RECURSIVE ] with_query [, ...] ]
18	REPLACE [/+ plan_hint /] INTO table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]	18	REPLACE [/+ plan_hint /] INTO table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]
		19	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
19	{ DEFAULT VALUES	20	{ DEFAULT VALUES
20	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]	21	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]
21	\| query }	22	\| query }
	@@ -80,6 +81,12 @@ NULL。
80		81
81	取值范围：已存在的字段名。	82	取值范围：已存在的字段名。
82		83
		84	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		85	+
		86	+ 该子句用于插入identity列时的行为控制。
		87	+
		88	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		89	+
83	- expression	90	- expression
84		91
85	赋予对应column的一个有效表达式或值。	92	赋予对应column的一个有效表达式或值。
	@@ -118,7 +125,8 @@ NULL。
118		125
119	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>	126	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>
120		127
121	-```	128	+- replace into语句基础示例
		129	+```sql
122	-- 创建表test.	130	-- 创建表test.
123	openGauss=# CREATE TABLE test (col1 int PRIMARY KEY, col2 INT);	131	openGauss=# CREATE TABLE test (col1 int PRIMARY KEY, col2 INT);
124		132
	@@ -151,4 +159,20 @@ openGauss=# select * from test;
151	1 \| 5	159	1 \| 5
152	2 \| 6	160	2 \| 6
153	(4 rows)	161	(4 rows)
		162	+```
154		163
		164	+- OVERRIDING clause示例
		165	+```sql
		166	+openGauss=# CREATE TABLE test_t1 (a int GENERATED ALWAYS AS IDENTITY, b text, c int);
		167	+NOTICE: CREATE TABLE will create implicit sequence "test_t1_a_seq" for serial column "test_t1.a"
		168	+CREATE TABLE
		169	+openGauss=# REPLACE INTO test_t1 (a, b, c) VALUES (1, 'alice', 25); -- error
		170	+ERROR: cannot insert a non-DEFAULT value into column "a"
		171	+DETAIL: Column "a" is an identity column defined as "GENERATED ALWAYS".
		172	+HINT: Use OVERRIDING SYSTEM VALUE to override.
		173	+openGauss=# -- error REPLACE can not work on sequence!
		174	+openGauss=# REPLACE INTO test_t1 (a, b, c) OVERRIDING SYSTEM VALUE VALUES (1, 'alice', 25);
		175	+ERROR: REPLACE can not work on sequence!
		176	+openGauss=#
		177	+
		178	+```

Mdocs-lite/zh/sql_reference/alter_table.md+147-16

	@@ -221,6 +221,9 @@
221	\| ALTER [ COLUMN ] column_name SET ( {attribute_option = value} [, ... ] )	221	\| ALTER [ COLUMN ] column_name SET ( {attribute_option = value} [, ... ] )
222	\| ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )	222	\| ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )
223	\| ALTER [ COLUMN ] column_name SET STORAGE { PLAIN \| EXTERNAL \| EXTENDED \| MAIN }	223	\| ALTER [ COLUMN ] column_name SET STORAGE { PLAIN \| EXTERNAL \| EXTENDED \| MAIN }
		224	+ \| ALTER [ COLUMN ] column_name ADD GENERATED generated_when AS IDENTITY [ ( seq_options) ]
		225	+ \| ALTER [ COLUMN ] column_name alter_identity_column_options [ ... ]
		226	+ \| ALTER [ COLUMN ] column_name DROP IDENTITY [ IF EXISTS ]
224	```	227	```
225		228
226	[!NOTE]说明	229	[!NOTE]说明
	@@ -266,6 +269,8 @@
266	>	269	>
267	> 此子句与上一子句中“MODIFY column\_name data\_type”部分语法相同，语义功能不同，当GUC参数b\_format\_behavior\_compat\_options含有'enable\_modify\_column'选项时，将按照此子句功能处理。	270	> 此子句与上一子句中“MODIFY column\_name data\_type”部分语法相同，语义功能不同，当GUC参数b\_format\_behavior\_compat\_options含有'enable\_modify\_column'选项时，将按照此子句功能处理。
268	>	271	>
		272	+ > 不支持列的identity属性添加/修改和删除。
		273	+ >
269	>- CHANGE \[ COLUMN \] old\_column\_name new\_column\_name data\_type \[ CHARACTER SET \| CHARSET charset \] \[\{\[ COLLATE collation \] \| \[ column\_constraint \]\} \[ ... \] \] \[FIRST \| AFTER column\_name\]	274	>- CHANGE \[ COLUMN \] old\_column\_name new\_column\_name data\_type \[ CHARACTER SET \| CHARSET charset \] \[\{\[ COLLATE collation \] \| \[ column\_constraint \]\} \[ ... \] \] \[FIRST \| AFTER column\_name\]
270	>	275	>
271	> 修改表已存在字段的名称和定义，字段新名称不能是已有字段的名称，将用新名称和定义替换字段原名称和定义原字段上的索引、独立对象约束（例如：主键、唯一键、CHECK约束）等不会被删除。\[FIRST \| AFTER column\_name\]语法表示修改字段名称和定义的同时修改字段在表中的位置。	276	> 修改表已存在字段的名称和定义，字段新名称不能是已有字段的名称，将用新名称和定义替换字段原名称和定义原字段上的索引、独立对象约束（例如：主键、唯一键、CHECK约束）等不会被删除。\[FIRST \| AFTER column\_name\]语法表示修改字段名称和定义的同时修改字段在表中的位置。
	@@ -280,6 +285,8 @@
280	>	285	>
281	> 修改字段的字符集或字符序会将字段中的数据转换为新的字符集进行编码。	286	> 修改字段的字符集或字符序会将字段中的数据转换为新的字符集进行编码。
282	>	287	>
		288	+ > 不支持列的identity属性添加/修改和删除。
		289	+ >
283	>- DROP \[ COLUMN \] \[ IF EXISTS \] column\_name \[ RESTRICT \| CASCADE \]	290	>- DROP \[ COLUMN \] \[ IF EXISTS \] column\_name \[ RESTRICT \| CASCADE \]
284	>	291	>
285	> 从表中删除一个字段，和这个字段相关的索引和表约束也会被自动删除。如果任何表之外的对象依赖于这个字段，必须声明CASCADE ，比如视图。	292	> 从表中删除一个字段，和这个字段相关的索引和表约束也会被自动删除。如果任何表之外的对象依赖于这个字段，必须声明CASCADE ，比如视图。
	@@ -324,25 +331,40 @@
324	>- ALTER \[ COLUMN \] column\_name SET STORAGE \{ PLAIN \| EXTERNAL \| EXTENDED \| MAIN \}	331	>- ALTER \[ COLUMN \] column\_name SET STORAGE \{ PLAIN \| EXTERNAL \| EXTENDED \| MAIN \}
325	>	332	>
326	> 为一个字段设置存储模式。这个设置控制这个字段是内联保存还是保存在一个附属的表里，以及数据是否要压缩。仅支持对行存表的设置；对列存表没有意义，执行时报错。SET STORAGE本身并不改变表上的任何东西，只是设置将来的表操作时，建议使用的策略。	333	> 为一个字段设置存储模式。这个设置控制这个字段是内联保存还是保存在一个附属的表里，以及数据是否要压缩。仅支持对行存表的设置；对列存表没有意义，执行时报错。SET STORAGE本身并不改变表上的任何东西，只是设置将来的表操作时，建议使用的策略。
		334	+ >
		335	+ > - ALTER \[ COLUMN \] column\_name ADD GENERATED generated\_when AS IDENTITY \[ \( seq_options\) \]
		336	+ >
		337	+ > 添加identity属性，同时可以指定identity列的起始值，步长，最大值，最小值等属性。
		338	+ >
		339	+ > - ALTER \[ COLUMN \] column_name alter\_identity\_column\_options \[ ... \]
		340	+ >
		341	+ > 修改identity列的属性，序列的起始值，最大值，最小值，步长等。
		342	+ >
		343	+ > - ALTER \[ COLUMN \] column\_name DROP IDENTITY \[ IF EXISTS \]
		344	+ >
		345	+ > 删除某列的identity属性，如果列没有identity属性则报错，如果声明了`IF EXISTS`语法则会跳过；成功删除后，identity列所拥有的序列也会被删除，但是列的not null约束不变。
		346	+
327		347
328	- 其中列约束column\_constraint为：	348	- 其中列约束column\_constraint为：
329		349
330	```	350	```
331	[ CONSTRAINT constraint_name ]	351	[ CONSTRAINT constraint_name ]
332	- { NOT NULL \|	352	+ { NOT NULL \|
333	- NULL \|	353	+ NULL \|
334	- CHECK ( expression ) \|	354	+ CHECK ( expression ) \|
335	- DEFAULT default_expr \|	355	+ DEFAULT default_expr \|
336	- GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	356	+ GENERATED [ ALWAYS \| BY DEFAULT ] AS IDENTITY [ ( seq_options ) ] \|
337	- AUTO_INCREMENT \|	357	+ GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
338	- ON UPDATE update_expr \|	358	+ ON UPDATE update_expr \|
339	- UNIQUE [KEY] index_parameters \|	359	+ { UNIQUE [KEY] index_parameters [ ON filegroup ] \|
340	- PRIMARY KEY index_parameters \|	360	+ PRIMARY KEY index_parameters [ ON filegroup ]
341	- ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|	361	+ } [ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] \|
342	- REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]	362	+ REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]
343	- [ ON DELETE action ] [ ON UPDATE action ] }	363	+ [ ON DELETE action ] [ ON UPDATE action ] [ ENABLE ] } \|
344	- [ ENABLE [VALIDATE \| NOVALIDATE] \| DISABLE [VALIDATE \| NOVALIDATE] ]	364	+ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] Constraint constraint_name } \|
345	- [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ]	365	+ AUTO_INCREMENT \|
		366	+ ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|
		367	+ [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|
346	[ COMMENT 'text' ]	368	[ COMMENT 'text' ]
347	```	369	```
348		370
	@@ -376,13 +398,40 @@
376	[ COMMENT 'text' ]	398	[ COMMENT 'text' ]
377	```	399	```
378		400
379	- 其中索引参数index\_parameters为：	401	+- 其中索引参数index\_parameters为：
380		402
381	```	403	```
382	[ WITH ( {storage_parameter = value} [, ... ] ) ]	404	[ WITH ( {storage_parameter = value} [, ... ] ) ]
383	[ USING INDEX TABLESPACE tablespace_name ]	405	[ USING INDEX TABLESPACE tablespace_name ]
384	```	406	```
385		407
		408	+- 其中identity属性参数generated\_when为：
		409	+
		410	+ ```EBNF
		411	+ ALWAYS \| BY DEFAULT
		412	+ ```
		413	+
		414	+- 其中identity属性序列参数seq\_options为：
		415	+
		416	+ ```EBNF
		417	+ seq_option
		418	+ \| OWNED BY name
		419	+ \| RESTART [ WITH ] NumericOnly
		420	+ ;
		421	+
		422	+ seq_option:
		423	+ { MAXVALUE \| MINVALUE \| START WITH \| START \| INCREMENT [ BY ] \| CACHE } NumericOnly
		424	+ \| { NOMAXVALUE \| MINVALUE \| NO MAXVALUE \| NO MINVALUE \| NOCYCLE \| [ NO ] CYCLE }
		425	+ ```
		426	+
		427	+- 其中修改identity属性参数alter\_identity\_column\_options为：
		428	+
		429	+ ```EBNF
		430	+ RESTART [ WITH ] NumericOnly
		431	+ \| SET GENERATED generated_when
		432	+ \| SET seq_option
		433	+ ```
		434	+
386	- 重命名表。对名称的修改不会影响所存储的数据。	435	- 重命名表。对名称的修改不会影响所存储的数据。
387		436
388	```	437	```
	@@ -606,6 +655,26 @@
606		655
607	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。	656	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。
608		657
		658	+- GENERATED \[ ALWAYS \| BY DEFAULT \] AS IDENTITY \[ \( seq\_options \) \]
		659	+
		660	+ 该语句创建identity列，用于生成自增/自减的序列。
		661	+
		662	+ 若在插入时不指定此列的值（或者指定为DEFAULT），则会默认生成。
		663	+
		664	+ 当列定义为`GANERATED ALWAYS`时，若想插入用户值需要使用`OVERRIDING SYSTEM VALUE`子句，否则会报错，对于UPDATE只能更新为`DEFAULT`；
		665	+ 当列定义为`GANERATED BY DEFAULT`时，用户提供的值会优先于默认值。
		666	+
		667	+ `seq_options`可以用于指定序列的选项。
		668	+
		669	+ >[!NOTE]说明
		670	+ >
		671	+ >- 该列的数据类型仅为整型，NUMERIC类型，该列隐式包含`NOT NULL`约束。
		672	+ >- 无法同时定义default，serial，auto_increment，生成列，NULL约束。
		673	+ >- 序列生成非事务操作，当列/表约束检查失败，触发器失败时该列已生成的值不会回滚。
		674	+ >- 用户自定义的值不会影响该列的下一个值的生成，
		675	+ >- 可以定义多列，但同一列不能重复定义。
		676	+ >- 不支持分区表。
		677	+
609	- GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]	678	- GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]
610		679
611	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。	680	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。
	@@ -770,7 +839,8 @@
770		839
771	请参考CREATE TABLE的[示例](create_table.md##示例)。	840	请参考CREATE TABLE的[示例](create_table.md##示例)。
772		841
773	-```	842	+- add column first/after示例
		843	+```sql
774	-- 创建B模式数据库。	844	-- 创建B模式数据库。
775	openGauss=# create database test_first_after dbcompatibility 'b';	845	openGauss=# create database test_first_after dbcompatibility 'b';
776	openGauss=# \c test_first_after	846	openGauss=# \c test_first_after
	@@ -807,6 +877,67 @@ openGauss=# alter table t1 add constraint uniq_a unique (f1) invisible;
807	openGauss=# alter table t1 alter index uniq_a visible;	877	openGauss=# alter table t1 alter index uniq_a visible;
808	```	878	```
809		879
		880	+- 添加/修改/删除identity列
		881	+```sql
		882	+openGauss=# create table t1 (a int generated always as identity, b int);
		883	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq" for serial column "t1.a"
		884	+CREATE TABLE
		885	+openGauss=# \d+ t1
		886	+ Table "public.t1"
		887	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		888	+--------+---------+---------------------------------------+---------+--------------+-------------
		889	+ a \| integer \| not null generated always as identity \| plain \| \|
		890	+ b \| integer \| \| plain \| \|
		891	+Has OIDs: no
		892	+Options: orientation=row, compression=no
		893	+
		894	+openGauss=# alter table t1 add column c numeric(20, 0) generated by default as identity;
		895	+NOTICE: ALTER TABLE will create implicit sequence "t1_c_seq" for serial column "t1.c"
		896	+ALTER TABLE
		897	+openGauss=# \d+ t1
		898	+ Table "public.t1"
		899	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		900	+--------+---------------+-------------------------------------------+---------+--------------+-------------
		901	+ a \| integer \| not null generated always as identity \| plain \| \|
		902	+ b \| integer \| \| plain \| \|
		903	+ c \| numeric(20,0) \| not null generated by default as identity \| main \| \|
		904	+Has OIDs: no
		905	+Options: orientation=row, compression=no
		906	+
		907	+openGauss=# alter table t1 alter column c set generated always set start with 10;
		908	+ALTER TABLE
		909	+openGauss=# \d+ t1
		910	+ Table "public.t1"
		911	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		912	+--------+---------------+---------------------------------------+---------+--------------+-------------
		913	+ a \| integer \| not null generated always as identity \| plain \| \|
		914	+ b \| integer \| \| plain \| \|
		915	+ c \| numeric(20,0) \| not null generated always as identity \| main \| \|
		916	+Has OIDs: no
		917	+Options: orientation=row, compression=no
		918	+
		919	+openGauss=# alter table t1 alter column b drop identity;
		920	+ERROR: column "b" of relation "t1" is not an identity column
		921	+openGauss=# alter table t1 alter column b drop identity if exists;
		922	+NOTICE: column "b" of relation "t1" is not an identity column, skipping
		923	+ALTER TABLE
		924	+openGauss=# alter table t1 alter column c drop identity;
		925	+ALTER TABLE
		926	+openGauss=# alter table t1 alter column c add generated by default as identity(start with 10 increment 20);
		927	+NOTICE: ALTER TABLE will create implicit sequence "t1_c_seq1" for serial column "t1.c"
		928	+ALTER TABLE
		929	+openGauss=# \d+ t1
		930	+ Table "public.t1"
		931	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		932	+--------+---------------+-------------------------------------------+---------+--------------+-------------
		933	+ a \| integer \| not null generated always as identity \| plain \| \|
		934	+ b \| integer \| \| plain \| \|
		935	+ c \| numeric(20,0) \| not null generated by default as identity \| main \| \|
		936	+Has OIDs: no
		937	+Options: orientation=row, compression=no
		938	+
		939	+```
		940	+
810	## 相关链接	941	## 相关链接
811		942
812	<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s489a6430be6447c193a4011257dc4994"></a>	943	<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s489a6430be6447c193a4011257dc4994"></a>

Mdocs-lite/zh/sql_reference/merge_into.md+66-3

	@@ -22,8 +22,9 @@ ON ( condition )
22	]	22	]
23	[	23	[
24	WHEN NOT MATCHED THEN	24	WHEN NOT MATCHED THEN
25	- INSERT { DEFAULT VALUES \|	25	+ INSERT [ ( column_name [, ...] ) ]
26	- [ ( column_name [, ...] ) ] VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }	26	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
		27	+ { DEFAULT VALUES \| VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }
27	];	28	];
28	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!	29	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!
29	```	30	```
	@@ -83,6 +84,12 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
83		84
84	WHEN MATCHED和WHEN NOT MATCHED子句顺序可以交换，可以缺省其中一个，但不能同时缺省，不支持同时指定两个WHEN MATCHED或WHEN NOT MATCHED子句。	85	WHEN MATCHED和WHEN NOT MATCHED子句顺序可以交换，可以缺省其中一个，但不能同时缺省，不支持同时指定两个WHEN MATCHED或WHEN NOT MATCHED子句。
85		86
		87	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		88	+
		89	+ 该子句用于插入identity列时的行为控制。
		90	+
		91	+ `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		92	+
86	- DEFAULT	93	- DEFAULT
87		94
88	用对应字段的缺省值填充该字段。	95	用对应字段的缺省值填充该字段。
	@@ -95,7 +102,8 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
95		102
96	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>	103	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>
97		104
98	-```	105	+- merge into语句基础示例
		106	+```sql
99	-- 创建目标表products和源表newproducts，并插入数据	107	-- 创建目标表products和源表newproducts，并插入数据
100	openGauss=# CREATE TABLE products	108	openGauss=# CREATE TABLE products
101	(	109	(
	@@ -148,3 +156,58 @@ openGauss=# SELECT * FROM products ORDER BY product_id;
148	openGauss=# DROP TABLE products;	156	openGauss=# DROP TABLE products;
149	openGauss=# DROP TABLE newproducts;	157	openGauss=# DROP TABLE newproducts;
150	```	158	```
		159	+
		160	+- merge into when not matched then insert overriding clause示例
		161	+```sql
		162	+openGauss=# create table target_table (
		163	+openGauss(# id int GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
		164	+openGauss(# name varchar(50),
		165	+openGauss(# age int
		166	+openGauss(# );
		167	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq" for serial column "target_table.id"
		168	+NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "target_table_pkey" for table "target_table"
		169	+CREATE TABLE
		170	+openGauss=# create table source_table (id int, name varchar(50), age int);
		171	+CREATE TABLE
		172	+openGauss=# insert into source_table values (10, 'zliu', 28), (11, 'sqi', 30);
		173	+INSERT 0 2
		174	+openGauss=# -- expected: success. let id generated by system.
		175	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		176	+openGauss-# when not matched then
		177	+openGauss-# insert (name, age) values (s.name, s.age);
		178	+MERGE 2
		179	+openGauss=# -- expected: error
		180	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		181	+openGauss-# when not matched then
		182	+openGauss-# insert (id, name, age) values (1, 'error', 21);
		183	+ERROR: cannot insert a non-DEFAULT value into column "id"
		184	+DETAIL: Column "id" is an identity column defined as "GENERATED ALWAYS".
		185	+HINT: Use OVERRIDING SYSTEM VALUE to override
		186	+openGauss=# -- expected: success
		187	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		188	+openGauss-# when not matched then
		189	+openGauss-# insert (id, name, age) OVERRIDING USER VALUE values (1, 'success', 22); -- 3
		190	+MERGE 2
		191	+openGauss=# -- expected: error
		192	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		193	+openGauss-# when not matched then
		194	+openGauss-# insert (id, name, age) OVERRIDING SYSTEM VALUE values (2, 'error', 23);
		195	+ERROR: duplicate key value violates unique constraint "target_table_pkey"
		196	+DETAIL: Key (id)=(2) already exists.
		197	+openGauss=# -- expected: error
		198	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		199	+openGauss-# when not matched then
		200	+openGauss-# insert (id, name, age) OVERRIDING SYSTEM VALUE values (3, 'error', 24);
		201	+ERROR: duplicate key value violates unique constraint "target_table_pkey"
		202	+DETAIL: Key (id)=(3) already exists.
		203	+openGauss=# select * from target_table order by 1,2,3;
		204	+ id \| name \| age
		205	+----+---------+-----
		206	+ 1 \| zliu \| 28
		207	+ 2 \| sqi \| 30
		208	+ 3 \| success \| 22
		209	+ 4 \| success \| 22
		210	+(4 rows)
		211	+
		212	+```
		213	+

Mdocs/zh/database_reference/PG_ATTRIBUTE.md+14-0

	@@ -190,5 +190,19 @@ PG\_ATTRIBUTE系统表存储关于表字段的信息。
190	<p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a>3. ATT_KV_TIMETAG：时间列。</p>	190	<p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p173371358124510"></a>3. ATT_KV_TIMETAG：时间列。</p>
191	</td>	191	</td>
192	</tr>	192	</tr>
		193	+<tr id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_row1718431494418"><td class="cellrowborder" valign="top" width="14.499999999999998%" headers="mcps1.2.4.1.1 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a>attdroppedname</p>
		194	+</td>
		195	+<td class="cellrowborder" valign="top" width="17.919999999999998%" headers="mcps1.2.4.1.2 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a>name</p>
		196	+</td>
		197	+<td class="cellrowborder" valign="top" width="67.58%" headers="mcps1.2.4.1.3 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a>被删除前的字段名</p>
		198	+</td>
		199	+</tr>
		200	+<tr id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_row1718431494418"><td class="cellrowborder" valign="top" width="14.499999999999998%" headers="mcps1.2.4.1.1 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p51842014164410"></a>attidentity</p>
		201	+</td>
		202	+<td class="cellrowborder" valign="top" width="17.919999999999998%" headers="mcps1.2.4.1.2 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p6184101464413"></a>char</p>
		203	+</td>
		204	+<td class="cellrowborder" valign="top" width="67.58%" headers="mcps1.2.4.1.3 "><p id="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a><a name="zh-cn_topic_0283137510_zh-cn_topic_0237122272_p11841145443"></a>某一列的identity属性, 取值为'a','d'或者'm'</p>
		205	+</td>
		206	+</tr>
193	</tbody>	207	</tbody>
194	</table>	208	</table>

Mdocs/zh/extension_reference/shark-ALTER-TABLE.md+64-22

	@@ -30,6 +30,7 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
30		30
31	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。	31	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。
32	- filegroup为任意字符串，支持通过[]包裹。	32	- filegroup为任意字符串，支持通过[]包裹。
		33	+- 新增支持为列添加identity属性的语法。
33		34
34	## 语法格式<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s58bdce220c9f4292ba9af919b04ad25c"></a>	35	## 语法格式<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s58bdce220c9f4292ba9af919b04ad25c"></a>
35		36
	@@ -89,21 +90,23 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
89		90
90	```	91	```
91	[ CONSTRAINT constraint_name ]	92	[ CONSTRAINT constraint_name ]
92	- { NOT NULL \|	93	+ { NOT NULL \|
93	- NULL \|	94	+ NULL \|
94	- CHECK ( expression ) \|	95	+ CHECK ( expression ) \|
95	- DEFAULT default_expr \|	96	+ DEFAULT default_expr \|
96	- GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	97	+ IDENTITY [ ( seed, increment ) ] \|
97	- AUTO_INCREMENT \|	98	+ GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
98	- ON UPDATE update_expr \|	99	+ ON UPDATE update_expr \|
99	- UNIQUE [KEY] index_parameters [ ON filegroup ] \|	100	+ { UNIQUE [KEY] index_parameters [ ON filegroup ] \|
100	- PRIMARY KEY index_parameters [ ON filegroup ] \|	101	+ PRIMARY KEY index_parameters [ ON filegroup ]
101	- ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|	102	+ } [ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] \|
102	- REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]	103	+ REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]
103	- [ ON DELETE action ] [ ON UPDATE action ] }	104	+ [ ON DELETE action ] [ ON UPDATE action ] [ ENABLE ] \|
104	- [ ENABLE [VALIDATE \| NOVALIDATE] \| DISABLE [VALIDATE \| NOVALIDATE] ]	105	+ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] Constraint constraint_name \|
105	- [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|	106	+ DEFAULT (expression) FOR (column_name) } \|
106	- DEFAULT (expression) FOR (column_name)	107	+ AUTO_INCREMENT \|
		108	+ ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|
		109	+ [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|
107	[ COMMENT 'text' ]	110	[ COMMENT 'text' ]
108	```	111	```
109		112
	@@ -211,12 +214,17 @@ COMPRESSION_DELAY选项的取值delay为[0, 10080]的整数;
211	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。	214	- 修改表语句中，针对UNIQUE和PRIMARY KEY约束，支持ON {filegroup \| "default" } 选项，无实际作用，仅语法支持。
212	- filegroup为任意字符串，支持通过[]包裹。	215	- filegroup为任意字符串，支持通过[]包裹。
213		216
214	-- DEFAULT (expression) FOR (column_name)	217	+- DEFAULT \( expression \) FOR \( column_name \)
215		218
216	- 该语法可以为指定列添加DEFAULT约束，该约束为一个表达式。	219	- 该语法可以为指定列添加DEFAULT约束，该约束为一个表达式。
217	- 对于显式声明约束名的场景，仅做语法支持，使用该语法创建的DEFAULT约束无法通过约束名进行删除。	220	- 对于显式声明约束名的场景，仅做语法支持，使用该语法创建的DEFAULT约束无法通过约束名进行删除。
218		221
219	-## opt\_clustered示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	222	+- IDENTITY \[ ( seed, increment ) \]
		223	+
		224	+ - 该语法为列添加identity属性，序列值递增，`seed`指定起始值，`increment`指定步长。
		225	+ - 一张表只能定义一列（包括generated as identity）。
		226	+
		227	+## opt\_clustered示例
220		228
221	```	229	```
222	openGauss=# CREATE TABLE alter_table_tbl1 (a INT, b INT);	230	openGauss=# CREATE TABLE alter_table_tbl1 (a INT, b INT);
	@@ -224,9 +232,9 @@ openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_a UNIQUE
224	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_b PRIMARY KEY NONCLUSTERED (a);	232	openGauss=# ALTER TABLE alter_table_tbl1 ADD CONSTRAINT alter_table_tbl_b PRIMARY KEY NONCLUSTERED (a);
225	```	233	```
226		234
227	-## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	235	+## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例
228		236
229	-```	237	+```sql
230	create table test1(col1 int primary key with(fillfactor = 20), col2 int);	238	create table test1(col1 int primary key with(fillfactor = 20), col2 int);
231	NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test1_pkey" for table "test1"	239	NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test1_pkey" for table "test1"
232		240
	@@ -251,9 +259,9 @@ NOTICE: parameter "data_compression" is currently ignored.
251	NOTICE: ALTER TABLE / ADD PRIMARY KEY will create implicit index "test3_pkey" for table "test3"	259	NOTICE: ALTER TABLE / ADD PRIMARY KEY will create implicit index "test3_pkey" for table "test3"
252	```	260	```
253		261
254	-## filegroup示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	262	+## filegroup示例
255		263
256	-```	264	+```sql
257	create table test1(col1 int primary key with(fillfactor = 20), col2 int);	265	create table test1(col1 int primary key with(fillfactor = 20), col2 int);
258		266
259	alter table test1 add constraint unique_name unique(col2) with (fillfactor = 50, ignore_dup_key = on) on [primary1];	267	alter table test1 add constraint unique_name unique(col2) with (fillfactor = 50, ignore_dup_key = on) on [primary1];
	@@ -268,10 +276,44 @@ create table test3(col1 int, col2 int);
268		276
269	alter table test3 add column col3 int primary key with (data_compression = none) on [primar4];	277	alter table test3 add column col3 int primary key with (data_compression = none) on [primar4];
270	```	278	```
		279	+## IDENTITY \[ \( seed, increment \) \] 示例
		280	+```sql
		281	+openGauss=# create extension shark;
		282	+CREATE EXTENSION
		283	+openGauss=# create table t1 (a int identity(10, 20), b int);
		284	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq_identity" for serial column "t1.a"
		285	+CREATE TABLE
		286	+openGauss=# \d+ t1
		287	+ Table "public.t1"
		288	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		289	+--------+---------+-------------------+---------+--------------+-------------
		290	+ a \| integer \| not null identity \| plain \| \|
		291	+ b \| integer \| \| plain \| \|
		292	+Has OIDs: no
		293	+Options: orientation=row, compression=no, collate=1537
		294	+Character Set: UTF8
		295	+Collate: utf8mb4_general_ci
271		296
272	-## DEFAULT (expression) FOR (column_name) 示例<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	297	+openGauss=# alter table t1 alter column b add identity ;
		298	+NOTICE: ALTER TABLE will create implicit sequence "t1_b_seq_identity" for serial column "t1.b"
		299	+ERROR: Multiple identity columns specified for table "t1". Only one identity column per table is allowed.
		300	+openGauss=# create table t2 (a int, b int);
		301	+CREATE TABLE
		302	+openGauss=# alter table t2 alter column b add identity ;
		303	+NOTICE: ALTER TABLE will create implicit sequence "t2_b_seq_identity" for serial column "t2.b"
		304	+ERROR: column "b" of relation "t2" must be declared NOT NULL before identity can be added
		305	+openGauss=# alter table t2 alter column b set not null;
		306	+ALTER TABLE
		307	+openGauss=# alter table t2 alter column b add identity ;
		308	+NOTICE: ALTER TABLE will create implicit sequence "t2_b_seq_identity" for serial column "t2.b"
		309	+ALTER TABLE
		310	+openGauss=#
273		311
274	```	312	```
		313	+
		314	+## DEFAULT (expression) FOR (column_name) 示例
		315	+
		316	+```sql
275	openGauss=# create table ADD_DEFAULT(id int, v1 varchar(20), v2 float);	317	openGauss=# create table ADD_DEFAULT(id int, v1 varchar(20), v2 float);
276	CREATE TABLE	318	CREATE TABLE
277	openGauss=# \d+ ADD_DEFAULT	319	openGauss=# \d+ ADD_DEFAULT

Mdocs/zh/extension_reference/shark-CREATE-TABLE.md+43-3

	@@ -64,6 +64,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
64	NULL \|	64	NULL \|
65	CHECK ( expression ) \|	65	CHECK ( expression ) \|
66	DEFAULT default_expr \|	66	DEFAULT default_expr \|
		67	+ IDENTITY [ ( seed, increment ) ] \|
67	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	68	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
68	AS ( generation_expr ) [PERSISTED] \|	69	AS ( generation_expr ) [PERSISTED] \|
69	AUTO_INCREMENT \|	70	AUTO_INCREMENT \|
	@@ -101,6 +102,11 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
101		102
102	## 参数说明	103	## 参数说明
103		104
		105	+- IDENTITY \[ \( seed, increment \) \]
		106	+
		107	+ - 该语法为列添加identity属性，序列值递增，`seed`指定起始值，`increment`指定步长。
		108	+ - 一张表只能定义一列（包括generated as identity）。
		109	+
104	- AS \( generation\_expr \) \[PERSISTED\]	110	- AS \( generation\_expr \) \[PERSISTED\]
105		111
106	该子句为兼容D库的语法，将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，PERSISTED表示像普通列一样存储生成列的值。	112	该子句为兼容D库的语法，将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，PERSISTED表示像普通列一样存储生成列的值。
	@@ -201,6 +207,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
201	- table_constraint中，针对PRIMARY KEY和UNIQUE约束支持使用{ column_name [ ASC \| DESC ] }语法, 为主键和唯一键提供升序或降序约束。	207	- table_constraint中，针对PRIMARY KEY和UNIQUE约束支持使用{ column_name [ ASC \| DESC ] }语法, 为主键和唯一键提供升序或降序约束。
202		208
203	## 生成列示例	209	## 生成列示例
		210	+
204	```sql	211	```sql
205	opengauss=# CREATE TABLE Products(	212	opengauss=# CREATE TABLE Products(
206	opengauss(# QtyAvailable smallint,	213	opengauss(# QtyAvailable smallint,
	@@ -233,6 +240,39 @@ opengauss=# ALTER TABLE Products DROP unitprice;
233	ALTER TABLE	240	ALTER TABLE
234	```	241	```
235		242
		243	+## IDENTITY \[ \( seed, increment \) \] 示例
		244	+```sql
		245	+openGauss=# create extension shark;
		246	+CREATE EXTENSION
		247	+openGauss=# create table t1 (a int identity(10, 20), b int);
		248	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq_identity" for serial column "t1.a"
		249	+CREATE TABLE
		250	+openGauss=# \d+ t1
		251	+ Table "public.t1"
		252	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		253	+--------+---------+-------------------+---------+--------------+-------------
		254	+ a \| integer \| not null identity \| plain \| \|
		255	+ b \| integer \| \| plain \| \|
		256	+Has OIDs: no
		257	+Options: orientation=row, compression=no, collate=1537
		258	+Character Set: UTF8
		259	+Collate: utf8mb4_general_ci
		260	+
		261	+openGauss=# insert into t1(b) values(10);
		262	+INSERT 0 1
		263	+openGauss=# insert into t1(a, b) overriding system value values(12, 10);
		264	+INSERT 0 1
		265	+openGauss=# insert into t1 default values;
		266	+INSERT 0 1
		267	+openGauss=# select * from t1;
		268	+ a \| b
		269	+----+----
		270	+ 10 \| 10
		271	+ 12 \| 10
		272	+ 30 \|
		273	+(3 rows)
		274	+
		275	+```
236	## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例	276	## WITH \( \{ storage\_parameter = value \} \[, ... \] \)示例
237		277
238	```sql	278	```sql
	@@ -315,7 +355,7 @@ Options: orientation=row, compression=no
315		355
316	```	356	```
317		357
318	-## 使用特殊前缀创建本地和全局临时表<a name="zh-cn_topic_0283136578_zh-cn_topic_0237122106_zh-cn_topic_0059777455_s985289833081489e9d77c485755bd362"></a>	358	+## 使用特殊前缀创建本地和全局临时表
319		359
320	```sql	360	```sql
321	openGauss=# CREATE TEMPORARY TABLE #ltt1	361	openGauss=# CREATE TEMPORARY TABLE #ltt1
	@@ -325,7 +365,7 @@ openGauss=# CREATE TEMPORARY TABLE #ltt1
325	ADDRESS VARCHAR(50) ,	365	ADDRESS VARCHAR(50) ,
326	POSTCODE CHAR(6)	366	POSTCODE CHAR(6)
327	) ON COMMIT PRESERVE ROWS;	367	) ON COMMIT PRESERVE ROWS;
328	-	368	+CREATE TABLE
329	openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1	369	openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1
330	(	370	(
331	ID INTEGER NOT NULL,	371	ID INTEGER NOT NULL,
	@@ -333,7 +373,7 @@ openGauss=# CREATE GLOBAL TEMPORARY TABLE ##gtt1
333	ADDRESS VARCHAR(50) ,	373	ADDRESS VARCHAR(50) ,
334	POSTCODE CHAR(6)	374	POSTCODE CHAR(6)
335	) ON COMMIT PRESERVE ROWS;	375	) ON COMMIT PRESERVE ROWS;
336	-	376	+CREATE TABLE
337	```	377	```
338		378
339	## 相关链接<a name="section156744489391"></a>	379	## 相关链接<a name="section156744489391"></a>

Mdocs/zh/extension_reference/shark-INSERT.md+66-2

 ```
 [ WITH [ RECURSIVE ] with_query [, ...] ]
 INSERT [/*+ plan_hint */] [INTO] table_name [partition_clause] [ AS alias ] [table_hint_clause] [ ( column_name [, ...] ) ]
++    [ OVERRIDING { SYSTEM | USER } VALUE ]
     { DEFAULT VALUES
     | VALUES {( { expression | DEFAULT } [, ...] ) }[, ...]
     | query }
     - 针对hint，会打印相关NOTICE信息。
++- **OVERRIDING \{ SYSTEM | USER \} VALUE**
++    该子句用于插入identity列时的行为控制。
++
++    - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
++    - 当开启`identity_insert`时可以插入用户值（包括default），否则只有使用`OVERRIDING SYSTEM VALUE`才能插入用户值，而insert overriding user value会忽略用户的值采用序列的值。
++
++## table_hint子句示例
++
++```sql
 create table t1(c1 int, c2 int);
 insert into t1 values(1, 2);
 NOTICE:  The nowait option is currently ignored
 ```
++## identity_insert 与 OVERRIDING clause 示例
++```sql
++openGauss=# create extension shark;
++CREATE EXTENSION
++openGauss=#  CREATE TABLE book(bookId int IDENTITY, bookname NVARCHAR(50), author NVARCHAR(50));
++NOTICE:  CREATE TABLE will create implicit sequence "book_bookid_seq_identity" for serial column "book.bookid"
++CREATE TABLE
++openGauss=# \d+ book
++                                               Table "public.book"
++  Column  |     Type      |                   Modifiers                   | Storage  | Stats target | Description
++----------+---------------+-----------------------------------------------+----------+--------------+-------------
++ bookid   | integer       | not null identity                             | plain    |              |
++ bookname | nvarchar2(50) | character set UTF8 collate utf8mb4_general_ci | extended |              |
++ author   | nvarchar2(50) | character set UTF8 collate utf8mb4_general_ci | extended |              |
++Has OIDs: no
++Options: orientation=row, compression=no, collate=1537
++Character Set: UTF8
++Collate: utf8mb4_general_ci
++
++openGauss=# set identity_insert = off;
++SET
++openGauss=# INSERT INTO book VALUES (2, 'xxx', 'xxx'); -- error;
++ERROR:  INSERT has more expressions than target columns
++LINE 1: INSERT INTO book VALUES (2, 'xxx', 'xxx');
++                                           ^
++openGauss=# INSERT INTO book (bookid, bookname, author) VALUES(11111, 'xxxx', 'xxx'); -- error, turn on identity_insert or use OVERRIDING
++ERROR:  cannot insert a non-DEFAULT value into column "bookid"
++DETAIL:  Column "bookid" is an identity column defined as "IDENTITY".
++HINT:  Use OVERRIDING SYSTEM VALUE to override, Or turn on "identity_insert".
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING SYSTEM VALUE VALUES (33, 'xxx', 'xxx'); -- success; -- 33
++INSERT 0 1
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING USER VALUE VALUES (11111, 'xxx', 'xxx'); -- success; -- 1
++INSERT 0 1
++openGauss=# set identity_insert = on;
++SET
++openGauss=# INSERT INTO book VALUES (44, 'xxx', 'xxx'); -- error;
++ERROR:  INSERT has more expressions than target columns
++LINE 1: INSERT INTO book VALUES (44, 'xxx', 'xxx');
++                                            ^
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING USER VALUE VALUES (11111, 'xxx', 'xxx'); -- success; -- 2
++INSERT 0 1
++openGauss=# INSERT INTO book (bookid, bookname, author) OVERRIDING SYSTEM VALUE VALUES (55, 'xxx', 'xxx'); -- success; -- 55
++INSERT 0 1
++openGauss=# set identity_insert = off;
++SET
++openGauss=# select * from book order by 1, 2;
++ bookid | bookname | author
++--------+----------+--------
++      1 | xxx      | xxx
++      2 | xxx      | xxx
++     33 | xxx      | xxx
++     55 | xxx      | xxx
++(4 rows)
++
++```
++
 ## 相关链接<a name="section156744489391"></a>
 [INSERT](../sql_reference/insert.md)

Mdocs/zh/extension_reference/shark-MERGE-INTO.md+62-3

	@@ -24,8 +24,9 @@ ON ( condition )
24	]	24	]
25	[	25	[
26	WHEN NOT MATCHED THEN	26	WHEN NOT MATCHED THEN
27	- INSERT { DEFAULT VALUES \|	27	+ INSERT [ ( column_name [, ...] ) ]
28	- [ ( column_name [, ...] ) ] VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }	28	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
		29	+ { DEFAULT VALUES \| VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }
29	];	30	];
30	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!	31	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!
31	```	32	```
	@@ -50,9 +51,18 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
50		51
51	- 针对hint，会打印相关NOTICE信息。	52	- 针对hint，会打印相关NOTICE信息。
52		53
		54	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		55	+
		56	+ 该子句用于插入identity列时的行为控制。
		57	+
		58	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		59	+ - 当开启`identity_insert`时可以插入用户值（包括default），否则只有使用`OVERRIDING SYSTEM VALUE`才能插入用户值，而insert overriding user value会忽略用户的值采用序列的值。
		60	+
		61	+
53	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>	62	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>
54		63
55	-```	64	+- merge into语句基础示例
		65	+```sql
56	-- 创建目标表products和源表newproducts，并插入数据	66	-- 创建目标表products和源表newproducts，并插入数据
57	openGauss=# CREATE TABLE products	67	openGauss=# CREATE TABLE products
58	(	68	(
	@@ -154,6 +164,55 @@ openGauss=# DROP TABLE products;
154	openGauss=# DROP TABLE newproducts;	164	openGauss=# DROP TABLE newproducts;
155	```	165	```
156		166
		167	+- identity_insert 与 OVERRIDING clause 示例
		168	+```sql
		169	+openGauss=# create table target_table ( id int identity, name varhcar(50), age int);
		170	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq_identity" for serial column "target_table.id"
		171	+ERROR: type "varhcar" does not exist
		172	+LINE 1: create table target_table ( id int identity, name varhcar(50...
		173	+ ^
		174	+openGauss=# create table target_table ( id int identity, name varchar(50), age int);
		175	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq_identity" for serial column "target_table.id"
		176	+CREATE TABLE
		177	+openGauss=# create table source_table (id int, name varchar(50), age int);
		178	+CREATE TABLE
		179	+openGauss=# insert into source_table values (10, 'zliu', 28), (11, 'sqi', 30);
		180	+INSERT 0 2
		181	+openGauss=# set identity_insert = off;
		182	+SET
		183	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		184	+openGauss-# when not matched then
		185	+openGauss-# insert (name, age) values (s.name, s.age);
		186	+MERGE 2
		187	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		188	+openGauss-# when not matched then
		189	+openGauss-# insert (id, name, age) values (1, 'error', 21);
		190	+ERROR: cannot insert a non-DEFAULT value into column "id"
		191	+DETAIL: Column "id" is an identity column defined as "IDENTITY".
		192	+HINT: Use OVERRIDING SYSTEM VALUE to override, Or turn on "identity_insert"
		193	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		194	+openGauss-# when not matched then
		195	+openGauss-# insert (id, name, age) OVERRIDING USER VALUE values (1, 'success', 22); -- 3
		196	+MERGE 2
		197	+openGauss=# set identity_insert = on;
		198	+SET
		199	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		200	+openGauss-# when not matched then
		201	+openGauss-# insert (id, name, age) values (s.id + 2, 'success', s.age);
		202	+MERGE 2
		203	+openGauss=# select * from target_table order by 1, 2,3;
		204	+ id \| name \| age
		205	+----+---------+-----
		206	+ 1 \| zliu \| 28
		207	+ 2 \| sqi \| 30
		208	+ 3 \| success \| 22
		209	+ 4 \| success \| 22
		210	+ 12 \| success \| 28
		211	+ 13 \| success \| 30
		212	+(6 rows)
		213	+
		214	+```
		215	+
157	## 相关链接<a name="section156744489391"></a>	216	## 相关链接<a name="section156744489391"></a>
158		217
159	[MERGE INTO](../sql_reference/merge_into.md)	218	[MERGE INTO](../sql_reference/merge_into.md)

Mdocs/zh/sql_reference/alter_table.md+158-28

	@@ -238,23 +238,26 @@
238	其中列相关的操作column\_clause可以是以下子句之一：	238	其中列相关的操作column\_clause可以是以下子句之一：
239		239
240	```	240	```
241	-ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [ compress_mode ] [ COLLATE collation ] [ column_constraint [ ... ] ] [ FIRST \| AFTER column_name ]	241	+ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [ compress_mode ] [ COLLATE collation ] [column_constraint [ ... ] ] [ FIRST \| AFTER column_name ]
242	\| ADD [ IF NOT EXISTS ] column_name data_type [ compress_mode ] [, ...]	242	\| ADD [ IF NOT EXISTS ] column_name data_type [ compress_mode ] [, ...]
243	\| MODIFY column_name data_type	243	\| MODIFY column_name data_type
244	\| MODIFY column_name [ CONSTRAINT constraint_name ] NOT NULL [ ENABLE ]	244	\| MODIFY column_name [ CONSTRAINT constraint_name ] NOT NULL [ ENABLE ]
245	\| MODIFY column_name [ CONSTRAINT constraint_name ] NULL	245	\| MODIFY column_name [ CONSTRAINT constraint_name ] NULL
246	-\| MODIFY [ COLUMN ] column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [{[ COLLATE collation ] \| [ column_constraint ]} [ ... ] ] [FIRST \| AFTER column_name]	246	+\| MODIFY [ COLUMN ] column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [{[ COLLATE collation ] \| [ column_constraint ]} [ ... ] ][FIRST \| AFTER column_name]
247	-\| CHANGE [ COLUMN ] old_column_name new_column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [{[ COLLATE collation ] \| [ column_constraint ]} [ ... ] ] [FIRST \| AFTER column_name]	247	+\| CHANGE [ COLUMN ] old_column_name new_column_name data_type [ CHARACTER SET \| CHARSET [ = ] charset ] [{[ COLLATE collation ] \| [column_constraint ]} [ ... ] ] [FIRST \| AFTER column_name]
248	-\| DROP [ COLUMN ] [ IF EXISTS ] column_name [ RESTRICT \| CASCADE ]	248	+\| DROP [ COLUMN ] [ IF EXISTS ] column_name [ RESTRICT \| CASCADE ]
249	-\| ALTER [ COLUMN ] column_name [ SET DATA ] TYPE data_type [ COLLATE collation ] [ USING expression ]	249	+\| ALTER [ COLUMN ] column_name [ SET DATA ] TYPE data_type [ COLLATE collation ] [ USING expression ]
250	-\| ALTER [ COLUMN ] column_name { SET DEFAULT expression \| DROP DEFAULT }	250	+\| ALTER [ COLUMN ] column_name { SET DEFAULT expression \| DROP DEFAULT }
251	-\| ALTER [ COLUMN ] column_name { SET \| DROP } NOT NULL	251	+\| ALTER [ COLUMN ] column_name { SET \| DROP } NOT NULL
252	-\| ALTER [ COLUMN ] column_name SET STATISTICS [PERCENT] integer	252	+\| ALTER [ COLUMN ] column_name SET STATISTICS [PERCENT] integer
253	-\| ADD STATISTICS (( column_1_name, column_2_name [, ...] ))	253	+\| ADD STATISTICS (( column_1_name, column_2_name [, ...] ))
254	-\| DELETE STATISTICS (( column_1_name, column_2_name [, ...] ))	254	+\| DELETE STATISTICS (( column_1_name, column_2_name [, ...] ))
255	-\| ALTER [ COLUMN ] column_name SET ( {attribute_option = value} [, ... ] )	255	+\| ALTER [ COLUMN ] column_name SET ( {attribute_option = value} [, ... ] )
256	-\| ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )	256	+\| ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )
257	\| ALTER [ COLUMN ] column_name SET STORAGE { PLAIN \| EXTERNAL \| EXTENDED \| MAIN }	257	\| ALTER [ COLUMN ] column_name SET STORAGE { PLAIN \| EXTERNAL \| EXTENDED \| MAIN }
		258	+\| ALTER [ COLUMN ] column_name ADD GENERATED generated_when AS IDENTITY [ ( seq_options) ]
		259	+\| ALTER [ COLUMN ] column_name alter_identity_column_options [ ... ]
		260	+\| ALTER [ COLUMN ] column_name DROP IDENTITY [ IF EXISTS ]
258	```	261	```
259		262
260	> + ADD \[ COLUMN \] \[ IF NOT EXISTS \] column\_name data\_type [ CHARACTER SET \| CHARSET [ = ] charset ] \[ compress\_mode \] \[ COLLATE collation \] \[ column\_constraint \[ ... \] \] \[ FIRST \| AFTER column\_name\]	263	> + ADD \[ COLUMN \] \[ IF NOT EXISTS \] column\_name data\_type [ CHARACTER SET \| CHARSET [ = ] charset ] \[ compress\_mode \] \[ COLLATE collation \] \[ column\_constraint \[ ... \] \] \[ FIRST \| AFTER column\_name\]
	@@ -297,6 +300,8 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
297	>	300	>
298	> 此子句与上一子句中“MODIFY column\_name data\_type”部分语法相同，语义功能不同，当GUC参数b\_format\_behavior\_compat\_options含有'enable\_modify\_column'选项时，将按照此子句功能处理。	301	> 此子句与上一子句中“MODIFY column\_name data\_type”部分语法相同，语义功能不同，当GUC参数b\_format\_behavior\_compat\_options含有'enable\_modify\_column'选项时，将按照此子句功能处理。
299	>	302	>
		303	+> 不支持列的identity属性添加/修改和删除。
		304	+>
300	> + CHANGE \[ COLUMN \] old\_column\_name new\_column\_name data\_type \[ CHARACTER SET \| CHARSET charset \] \[\{\[ COLLATE collation \] \| \[ column\_constraint \]\} \[ ... \] \] \[FIRST \| AFTER column\_name\]	305	> + CHANGE \[ COLUMN \] old\_column\_name new\_column\_name data\_type \[ CHARACTER SET \| CHARSET charset \] \[\{\[ COLLATE collation \] \| \[ column\_constraint \]\} \[ ... \] \] \[FIRST \| AFTER column\_name\]
301	>	306	>
302	> 修改表已存在字段的名称和定义，字段新名称不能是已有字段的名称，将用新名称和定义替换字段原名称和定义原字段上的索引、独立对象约束（例如：主键、唯一键、CHECK约束）等不会被删除。\[FIRST \| AFTER column\_name\]语法表示修改字段名称和定义的同时修改字段在表中的位置。	307	> 修改表已存在字段的名称和定义，字段新名称不能是已有字段的名称，将用新名称和定义替换字段原名称和定义原字段上的索引、独立对象约束（例如：主键、唯一键、CHECK约束）等不会被删除。\[FIRST \| AFTER column\_name\]语法表示修改字段名称和定义的同时修改字段在表中的位置。
	@@ -311,6 +316,8 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
311	>	316	>
312	> 修改字段的字符集或字符序会将字段中的数据转换为新的字符集进行编码。	317	> 修改字段的字符集或字符序会将字段中的数据转换为新的字符集进行编码。
313	>	318	>
		319	+> 不支持列的identity属性添加/修改和删除。
		320	+>
314	> + DROP \[ COLUMN \] \[ IF EXISTS \] column\_name \[ RESTRICT \| CASCADE \]	321	> + DROP \[ COLUMN \] \[ IF EXISTS \] column\_name \[ RESTRICT \| CASCADE \]
315	>	322	>
316	> 从表中删除一个字段，和这个字段相关的索引和表约束也会被自动删除。如果任何表之外的对象依赖于这个字段，必须声明CASCADE ，比如视图。	323	> 从表中删除一个字段，和这个字段相关的索引和表约束也会被自动删除。如果任何表之外的对象依赖于这个字段，必须声明CASCADE ，比如视图。
	@@ -354,26 +361,40 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
354	>	361	>
355	> - ALTER \[ COLUMN \] column\_name SET STORAGE \{ PLAIN \| EXTERNAL \| EXTENDED \| MAIN \}	362	> - ALTER \[ COLUMN \] column\_name SET STORAGE \{ PLAIN \| EXTERNAL \| EXTENDED \| MAIN \}
356	>	363	>
357	-> 为一个字段设置存储模式。这个设置控制这个字段是内联保存还是保存在一个附属的表里，以及数据是否要压缩。仅支持对行存表的设置；对列存表没有意义，执行时报错。SET STORAGE本身并不改变表上的任何东西，只是设置将来的表操作时，建议使用的策略。	364	+> 为一个字段设置存储模式。这个设置控制这个字段是内联保存还是保存在一个附属的表里，以及数据是否要压缩。仅支持对行存表的设置；对列存表没有意义，执行时报错。SET STORAGE本身并不改变表上的任何东西，只是设置将来的表操作时，建议使用的策略。
		365	+>
		366	+> - ALTER \[ COLUMN \] column\_name ADD GENERATED generated\_when AS IDENTITY \[ \( seq_options\) \]
		367	+>
		368	+> 添加identity属性，同时可以指定identity列的起始值，步长，最大值，最小值等属性。
		369	+>
		370	+> - ALTER \[ COLUMN \] column_name alter\_identity\_column\_options \[ ... \]
		371	+>
		372	+> 修改identity列的属性，序列的起始值，最大值，最小值，步长等。
		373	+>
		374	+> - ALTER \[ COLUMN \] column\_name DROP IDENTITY \[ IF EXISTS \]
		375	+>
		376	+> 删除某列的identity属性，如果列没有identity属性则报错，如果声明了`IF EXISTS`语法则会跳过；成功删除后，identity列所拥有的序列也会被删除，但是列的not null约束不变。
358		377
359	- 其中列约束column\_constraint为：	378	- 其中列约束column\_constraint为：
360		379
361	```	380	```
362	[ CONSTRAINT constraint_name ]	381	[ CONSTRAINT constraint_name ]
363	- { NOT NULL \|	382	+ { NOT NULL \|
364	- NULL \|	383	+ NULL \|
365	- CHECK ( expression ) \|	384	+ CHECK ( expression ) \|
366	- DEFAULT default_expr \|	385	+ DEFAULT default_expr \|
367	- GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	386	+ GENERATED [ ALWAYS \| BY DEFAULT ] AS IDENTITY [ ( seq_options ) ] \|
368	- AUTO_INCREMENT \|	387	+ GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
369	- ON UPDATE update_expr \|	388	+ ON UPDATE update_expr \|
370	- UNIQUE [KEY] index_parameters \|	389	+ { UNIQUE [KEY] index_parameters [ ON filegroup ] \|
371	- PRIMARY KEY index_parameters \|	390	+ PRIMARY KEY index_parameters [ ON filegroup ]
372	- ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|	391	+ } [ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] \|
373	- REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]	392	+ REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL \| MATCH PARTIAL \| MATCH SIMPLE ]
374	- [ ON DELETE action ] [ ON UPDATE action ] }	393	+ [ ON DELETE action ] [ ON UPDATE action ] [ ENABLE ] } \|
375	- [ ENABLE [VALIDATE \| NOVALIDATE] \| DISABLE [VALIDATE \| NOVALIDATE] ]	394	+ { ENABLE \| DISABLE } [ VALIDATE \| NOVALIDATE ] Constraint constraint_name } \|
376	- [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ]	395	+ AUTO_INCREMENT \|
		396	+ ENCRYPTED WITH ( COLUMN_ENCRYPTION_KEY = column_encryption_key, ENCRYPTION_TYPE = encryption_type_value ) \|
		397	+ [ DEFERRABLE \| NOT DEFERRABLE \| INITIALLY DEFERRED \| INITIALLY IMMEDIATE ] \|
377	[ COMMENT 'text' ]	398	[ COMMENT 'text' ]
378	```	399	```
379		400
	@@ -411,6 +432,33 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
411	[ USING INDEX TABLESPACE tablespace_name ]	432	[ USING INDEX TABLESPACE tablespace_name ]
412	```	433	```
413		434
		435	+- 其中identity属性参数generated\_when为：
		436	+
		437	+ ```EBNF
		438	+ ALWAYS \| BY DEFAULT
		439	+ ```
		440	+
		441	+- 其中identity属性序列参数seq\_options为：
		442	+
		443	+ ```EBNF
		444	+ seq_option
		445	+ \| OWNED BY name
		446	+ \| RESTART [ WITH ] NumericOnly
		447	+ ;
		448	+
		449	+ seq_option:
		450	+ { MAXVALUE \| MINVALUE \| START WITH \| START \| INCREMENT [ BY ] \| CACHE } NumericOnly
		451	+ \| { NOMAXVALUE \| MINVALUE \| NO MAXVALUE \| NO MINVALUE \| NOCYCLE \| [ NO ] CYCLE }
		452	+ ```
		453	+
		454	+- 其中修改identity属性参数alter\_identity\_column\_options为：
		455	+
		456	+ ```EBNF
		457	+ RESTART [ WITH ] NumericOnly
		458	+ \| SET GENERATED generated_when
		459	+ \| SET seq_option
		460	+ ```
		461	+
414	- 重命名表。对名称的修改不会影响所存储的数据。	462	- 重命名表。对名称的修改不会影响所存储的数据。
415		463
416	```	464	```
	@@ -647,6 +695,26 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
647		695
648	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。	696	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。
649		697
		698	+- GENERATED \[ ALWAYS \| BY DEFAULT \] AS IDENTITY \[ \( seq\_options \) \]
		699	+
		700	+ 该语句创建identity列，用于生成自增/自减的序列。
		701	+
		702	+ 若在插入时不指定此列的值（或者指定为DEFAULT），则会默认生成。
		703	+
		704	+ 当列定义为`GANERATED ALWAYS`时，若想插入用户值需要使用`OVERRIDING SYSTEM VALUE`子句，否则会报错，对于UPDATE只能更新为`DEFAULT`；
		705	+ 当列定义为`GANERATED BY DEFAULT`时，用户提供的值会优先于默认值。
		706	+
		707	+ `seq_options`可以用于指定序列的选项。
		708	+
		709	+ >[!NOTE]说明
		710	+ >
		711	+ >- 该列的数据类型仅为整型，NUMERIC类型，该列隐式包含`NOT NULL`约束。
		712	+ >- 无法同时定义default，serial，auto_increment，生成列，NULL约束。
		713	+ >- 序列生成非事务操作，当列/表约束检查失败，触发器失败时该列已生成的值不会回滚。
		714	+ >- 用户自定义的值不会影响该列的下一个值的生成，
		715	+ >- 可以定义多列，但同一列不能重复定义。
		716	+ >- 不支持分区表。
		717	+
650	- GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]	718	- GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]
651		719
652	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。	720	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。
	@@ -808,7 +876,8 @@ ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ CHARACTER SET \| CHARSET
808		876
809	请参考CREATE TABLE的[示例](create_table.md#zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s86758dcf05d442d2a9ebd272e76ed1b8)。	877	请参考CREATE TABLE的[示例](create_table.md#zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s86758dcf05d442d2a9ebd272e76ed1b8)。
810		878
811	-```	879	+- add column first/after示例
		880	+```sql
812	-- 创建B模式数据库。	881	-- 创建B模式数据库。
813	openGauss=# create database test_first_after dbcompatibility 'b';	882	openGauss=# create database test_first_after dbcompatibility 'b';
814	openGauss=# \c test_first_after	883	openGauss=# \c test_first_after
	@@ -845,6 +914,67 @@ openGauss=# alter table t1 add constraint uniq_a unique (f1) invisible;
845	openGauss=# alter table t1 alter index uniq_a visible;	914	openGauss=# alter table t1 alter index uniq_a visible;
846	```	915	```
847		916
		917	+- 添加/修改/删除identity列
		918	+```sql
		919	+openGauss=# create table t1 (a int generated always as identity, b int);
		920	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq" for serial column "t1.a"
		921	+CREATE TABLE
		922	+openGauss=# \d+ t1
		923	+ Table "public.t1"
		924	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		925	+--------+---------+---------------------------------------+---------+--------------+-------------
		926	+ a \| integer \| not null generated always as identity \| plain \| \|
		927	+ b \| integer \| \| plain \| \|
		928	+Has OIDs: no
		929	+Options: orientation=row, compression=no
		930	+
		931	+openGauss=# alter table t1 add column c numeric(20, 0) generated by default as identity;
		932	+NOTICE: ALTER TABLE will create implicit sequence "t1_c_seq" for serial column "t1.c"
		933	+ALTER TABLE
		934	+openGauss=# \d+ t1
		935	+ Table "public.t1"
		936	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		937	+--------+---------------+-------------------------------------------+---------+--------------+-------------
		938	+ a \| integer \| not null generated always as identity \| plain \| \|
		939	+ b \| integer \| \| plain \| \|
		940	+ c \| numeric(20,0) \| not null generated by default as identity \| main \| \|
		941	+Has OIDs: no
		942	+Options: orientation=row, compression=no
		943	+
		944	+openGauss=# alter table t1 alter column c set generated always set start with 10;
		945	+ALTER TABLE
		946	+openGauss=# \d+ t1
		947	+ Table "public.t1"
		948	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		949	+--------+---------------+---------------------------------------+---------+--------------+-------------
		950	+ a \| integer \| not null generated always as identity \| plain \| \|
		951	+ b \| integer \| \| plain \| \|
		952	+ c \| numeric(20,0) \| not null generated always as identity \| main \| \|
		953	+Has OIDs: no
		954	+Options: orientation=row, compression=no
		955	+
		956	+openGauss=# alter table t1 alter column b drop identity;
		957	+ERROR: column "b" of relation "t1" is not an identity column
		958	+openGauss=# alter table t1 alter column b drop identity if exists;
		959	+NOTICE: column "b" of relation "t1" is not an identity column, skipping
		960	+ALTER TABLE
		961	+openGauss=# alter table t1 alter column c drop identity;
		962	+ALTER TABLE
		963	+openGauss=# alter table t1 alter column c add generated by default as identity(start with 10 increment 20);
		964	+NOTICE: ALTER TABLE will create implicit sequence "t1_c_seq1" for serial column "t1.c"
		965	+ALTER TABLE
		966	+openGauss=# \d+ t1
		967	+ Table "public.t1"
		968	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		969	+--------+---------------+-------------------------------------------+---------+--------------+-------------
		970	+ a \| integer \| not null generated always as identity \| plain \| \|
		971	+ b \| integer \| \| plain \| \|
		972	+ c \| numeric(20,0) \| not null generated by default as identity \| main \| \|
		973	+Has OIDs: no
		974	+Options: orientation=row, compression=no
		975	+
		976	+```
		977	+
848	## 相关链接<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s489a6430be6447c193a4011257dc4994"></a>	978	## 相关链接<a name="zh-cn_topic_0283137126_zh-cn_topic_0237122076_zh-cn_topic_0059779051_s489a6430be6447c193a4011257dc4994"></a>
849		979
850	[CREATE TABLE](create_table.md)，[DROP TABLE](drop_table.md)	980	[CREATE TABLE](create_table.md)，[DROP TABLE](drop_table.md)

Mdocs/zh/sql_reference/create_table.md+156-35

	@@ -50,6 +50,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
50	CHECK ( expression ) \|	50	CHECK ( expression ) \|
51	DEFAULT default_expr \|	51	DEFAULT default_expr \|
52	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|	52	GENERATED ALWAYS AS ( generation_expr ) [STORED] \|
		53	+ GENERATED [ ALWAYS \| BY DEFAULT ] AS IDENTITY [ ( seq_options ) ] \|
53	AUTO_INCREMENT \|	54	AUTO_INCREMENT \|
54	ON UPDATE update_expr \|	55	ON UPDATE update_expr \|
55	UNIQUE [KEY] index_parameters \|	56	UNIQUE [KEY] index_parameters \|
	@@ -85,7 +86,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
85	- 其中like选项like\_option为：	86	- 其中like选项like\_option为：
86		87
87	```	88	```
88	- { INCLUDING \| EXCLUDING } { DEFAULTS \| GENERATED \| CONSTRAINTS \| INDEXES \| STORAGE \| COMMENTS \| PARTITION \| RELOPTIONS \| ALL }	89	+ { INCLUDING \| EXCLUDING } { DEFAULTS \| GENERATED \| IDENTITY \| CONSTRAINTS \| INDEXES \| STORAGE \| COMMENTS \| PARTITION \| RELOPTIONS \| ALL }
89	```	90	```
90		91
91	- 其中索引参数index\_parameters为：	92	- 其中索引参数index\_parameters为：
	@@ -95,6 +96,13 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
95	[ USING INDEX TABLESPACE tablespace_name ]	96	[ USING INDEX TABLESPACE tablespace_name ]
96	```	97	```
97		98
		99	+- 其中seq\_options为：
		100	+ ```
		101	+ { MAXVALUE \| MINVALUE \| START WITH \| START \| INCREMENT [ BY ] \| CACHE \| RESTART [ WITH ] } NumericOnly
		102	+ \| { NOMAXVALUE \| MINVALUE \| NO MAXVALUE \| NO MINVALUE \| NOCYCLE \| [ NO ] CYCLE }
		103	+ \| OWNED BY name
		104	+ ```
		105	+
98	## 参数说明<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s99cf2ac11c79436c93385e4efd7c4428"></a>	106	## 参数说明<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s99cf2ac11c79436c93385e4efd7c4428"></a>
99		107
100	- UNLOGGED	108	- UNLOGGED
	@@ -311,7 +319,8 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
311	- INCLUDING ALL包含了INCLUDING DEFAULTS、INCLUDING CONSTRAINTS、INCLUDING INDEXES、INCLUDING STORAGE、INCLUDING COMMENTS、INCLUDING PARTITION和INCLUDING RELOPTIONS的内容。	319	- INCLUDING ALL包含了INCLUDING DEFAULTS、INCLUDING CONSTRAINTS、INCLUDING INDEXES、INCLUDING STORAGE、INCLUDING COMMENTS、INCLUDING PARTITION和INCLUDING RELOPTIONS的内容。
312	- ATUO_INCREMENT列需要为主键或唯一约束的第一个字段，若复制包含AUTO_INCREAMENT列的表时指定EXCLUDING INDEX，将会报错。其中AUTO_INCREAMENT只在B库中生效。	320	- ATUO_INCREMENT列需要为主键或唯一约束的第一个字段，若复制包含AUTO_INCREAMENT列的表时指定EXCLUDING INDEX，将会报错。其中AUTO_INCREAMENT只在B库中生效。
313	- 新表自动从这个表中继承所有字段名及其数据类型和非空约束，新表与源表之间在创建动作完毕之后是完全无关的。	321	- 新表自动从这个表中继承所有字段名及其数据类型和非空约束，新表与源表之间在创建动作完毕之后是完全无关的。
314	-	322	+ - INCLUDING IDENTITY用于复制表列的identity属性，会创建新的序列而不会复制潜在序列的选项，新序列选项默认。该选项不支持分区表。
		323	+
315	>[!TIP]须知	324	>[!TIP]须知
316	>	325	>
317	>- 如果源表包含serial、bigserial、smallserial、largeserial类型，或者源表字段的默认值是sequence，且sequence属于源表（通过CREATE SEQUENCE ... OWNED BY创建），这些Sequence不会关联到新表中，新表中会重新创建属于自己的sequence。这和之前版本的处理逻辑不同。如果用户希望源表和新表共享Sequence，需要首先创建一个共享的Sequence（避免使用OWNED BY），并配置为源表字段默认值，这样创建的新表会和源表共享该Sequence。	326	>- 如果源表包含serial、bigserial、smallserial、largeserial类型，或者源表字段的默认值是sequence，且sequence属于源表（通过CREATE SEQUENCE ... OWNED BY创建），这些Sequence不会关联到新表中，新表中会重新创建属于自己的sequence。这和之前版本的处理逻辑不同。如果用户希望源表和新表共享Sequence，需要首先创建一个共享的Sequence（避免使用OWNED BY），并配置为源表字段默认值，这样创建的新表会和源表共享该Sequence。
	@@ -323,7 +332,7 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
323	>- 如果源表是本地临时表，则新表也必须是本地临时表，否则会报错。	332	>- 如果源表是本地临时表，则新表也必须是本地临时表，否则会报错。
324	>	333	>
325	>- 如果源表是hash或list分区表，则在CREATE TABLE ... (LIKE ... INCLUDIING PARTITION)时会报错，不支持复制hash或list分区表的分区，仅支持range分区。对于二级分区表，同样只支持range-range二级分区。	334	>- 如果源表是hash或list分区表，则在CREATE TABLE ... (LIKE ... INCLUDIING PARTITION)时会报错，不支持复制hash或list分区表的分区，仅支持range分区。对于二级分区表，同样只支持range-range二级分区。
326	-	335	+
327	- WITH \( \{ storage\_parameter = value \} \[, ... \] \)	336	- WITH \( \{ storage\_parameter = value \} \[, ... \] \)
328		337
329	这个子句为表或索引指定一个可选的存储参数。用于表的WITH子句还可以包含OIDS=FALSE表示不分配OID。	338	这个子句为表或索引指定一个可选的存储参数。用于表的WITH子句还可以包含OIDS=FALSE表示不分配OID。
	@@ -495,9 +504,9 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
495	取值范围：on/off。	504	取值范围：on/off。
496		505
497	默认值：on。	506	默认值：on。
498	-	507	+
499	- + collate	508	+ - collate
500	-	509	+
501	在B模式数据库下（即sql\_compatibility = 'B'）用于记录表的默认字符序，一般只用于内部存储和导入导出，不推荐用户指定或修改。	510	在B模式数据库下（即sql\_compatibility = 'B'）用于记录表的默认字符序，一般只用于内部存储和导入导出，不推荐用户指定或修改。
502		511
503	取值范围：B模式数据库中独立支持的字符序的oid。	512	取值范围：B模式数据库中独立支持的字符序的oid。
	@@ -565,7 +574,8 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
565		574
566	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。	575	缺省表达式将被用于任何未声明该字段数值的插入操作。如果没有指定缺省值则缺省值为NULL 。
567		576
568	-+ GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]	577	+
		578	+- GENERATED ALWAYS AS \( generation\_expr \) \[STORED\]
569		579
570	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。	580	该子句将字段创建为生成列，生成列的值在写入（插入或更新）数据时由generation\_expr计算得到，STORED表示像普通列一样存储生成列的值。
571		581
	@@ -581,6 +591,26 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
581	>- 生成列的权限控制和普通列一样。	591	>- 生成列的权限控制和普通列一样。
582	>- 列存表、内存表MOT不支持生成列。外表中仅postgres\_fdw支持生成列。	592	>- 列存表、内存表MOT不支持生成列。外表中仅postgres\_fdw支持生成列。
583		593
		594	+- GENERATED \[ ALWAYS \| BY DEFAULT \] AS IDENTITY \[ \( seq\_options \) \]
		595	+
		596	+ 该语句创建identity列，用于生成自增/自减的序列。
		597	+
		598	+ 若在插入时不指定此列的值（或者指定为DEFAULT），则会默认生成。
		599	+
		600	+ 当列定义为`GANERATED ALWAYS`时，若想插入用户值需要使用`OVERRIDING SYSTEM VALUE`子句，否则会报错，对于UPDATE只能更新为`DEFAULT`；
		601	+ 当列定义为`GANERATED BY DEFAULT`时，用户提供的值会优先于默认值。
		602	+
		603	+ `seq_options`可以用于指定序列的选项。
		604	+
		605	+ >[!NOTE]说明
		606	+ >
		607	+ >- 该列的数据类型仅为整型，NUMERIC类型，该列隐式包含`NOT NULL`约束。
		608	+ >- 无法同时定义default，serial，auto_increment，生成列，NULL约束。
		609	+ >- 序列生成非事务操作，当列/表约束检查失败，触发器失败时该列已生成的值不会回滚。
		610	+ >- 用户自定义的值不会影响该列的下一个值的生成，
		611	+ >- 可以定义多列，但同一列不能重复定义。
		612	+ >- 不支持分区表。
		613	+
584	- AUTO\_INCREMENT	614	- AUTO\_INCREMENT
585		615
586	该关键字将字段指定为自动增长列。	616	该关键字将字段指定为自动增长列。
	@@ -700,8 +730,8 @@ CREATE [ [ GLOBAL \| LOCAL ] [ TEMPORARY \| TEMP ] \| UNLOGGED ] TABLE [ IF NOT EXI
700		730
701	## 示例<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s86758dcf05d442d2a9ebd272e76ed1b8"></a>	731	## 示例<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_s86758dcf05d442d2a9ebd272e76ed1b8"></a>
702		732
703	-```	733	+- 创建简单的表。
704	---创建简单的表。	734	+```sql
705	openGauss=# CREATE TABLE tpcds.warehouse_t1	735	openGauss=# CREATE TABLE tpcds.warehouse_t1
706	(	736	(
707	W_WAREHOUSE_SK INTEGER NOT NULL,	737	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -739,8 +769,8 @@ openGauss=# CREATE TABLE tpcds.warehouse_t2
739	);	769	);
740	```	770	```
741		771
742	-```	772	+- 创建表，并指定W_STATE字段的缺省值为GA。
743	---创建表，并指定W_STATE字段的缺省值为GA。	773	+```sql
744	openGauss=# CREATE TABLE tpcds.warehouse_t3	774	openGauss=# CREATE TABLE tpcds.warehouse_t3
745	(	775	(
746	W_WAREHOUSE_SK INTEGER NOT NULL,	776	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -779,8 +809,8 @@ openGauss=# CREATE TABLE tpcds.warehouse_t4
779	);	809	);
780	```	810	```
781		811
782	-```	812	+- 创建一个带有70%填充因子的表。
783	---创建一个带有70%填充因子的表。	813	+```sql
784	openGauss=# CREATE TABLE tpcds.warehouse_t5	814	openGauss=# CREATE TABLE tpcds.warehouse_t5
785	(	815	(
786	W_WAREHOUSE_SK INTEGER NOT NULL,	816	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -819,7 +849,10 @@ openGauss=# CREATE TABLE tpcds.warehouse_t6
819	W_GMT_OFFSET DECIMAL(5,2)	849	W_GMT_OFFSET DECIMAL(5,2)
820	) WITH(fillfactor=70);	850	) WITH(fillfactor=70);
821		851
822	---创建表，并指定该表数据不写入预写日志。	852	+```
		853	+
		854	+- 创建表，并指定该表数据不写入预写日志。
		855	+```sql
823	openGauss=# CREATE UNLOGGED TABLE tpcds.warehouse_t7	856	openGauss=# CREATE UNLOGGED TABLE tpcds.warehouse_t7
824	(	857	(
825	W_WAREHOUSE_SK INTEGER NOT NULL,	858	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -837,8 +870,10 @@ openGauss=# CREATE UNLOGGED TABLE tpcds.warehouse_t7
837	W_COUNTRY VARCHAR(20) ,	870	W_COUNTRY VARCHAR(20) ,
838	W_GMT_OFFSET DECIMAL(5,2)	871	W_GMT_OFFSET DECIMAL(5,2)
839	);	872	);
		873	+```
840		874
841	---创建表临时表。	875	+- 创建表临时表。
		876	+```sql
842	openGauss=# CREATE TEMPORARY TABLE warehouse_t24	877	openGauss=# CREATE TEMPORARY TABLE warehouse_t24
843	(	878	(
844	W_WAREHOUSE_SK INTEGER NOT NULL,	879	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -885,7 +920,10 @@ openGauss=# CREATE GLOBAL TEMPORARY TABLE gtt1
885	POSTCODE CHAR(6)	920	POSTCODE CHAR(6)
886	) ON COMMIT PRESERVE ROWS;	921	) ON COMMIT PRESERVE ROWS;
887		922
888	---创建表时，不希望因为表已存在而报错。	923	+```
		924	+
		925	+- 创建表时，不希望因为表已存在而报错。
		926	+```sql
889	openGauss=# CREATE TABLE IF NOT EXISTS tpcds.warehouse_t8	927	openGauss=# CREATE TABLE IF NOT EXISTS tpcds.warehouse_t8
890	(	928	(
891	W_WAREHOUSE_SK INTEGER NOT NULL,	929	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -903,8 +941,10 @@ openGauss=# CREATE TABLE IF NOT EXISTS tpcds.warehouse_t8
903	W_COUNTRY VARCHAR(20) ,	941	W_COUNTRY VARCHAR(20) ,
904	W_GMT_OFFSET DECIMAL(5,2)	942	W_GMT_OFFSET DECIMAL(5,2)
905	);	943	);
		944	+```
906		945
907	---创建普通表空间。	946	+- 创建普通表空间。
		947	+```sql
908	openGauss=# CREATE TABLESPACE DS_TABLESPACE1 RELATIVE LOCATION 'tablespace/tablespace_1';	948	openGauss=# CREATE TABLESPACE DS_TABLESPACE1 RELATIVE LOCATION 'tablespace/tablespace_1';
909	--创建表时，指定表空间。	949	--创建表时，指定表空间。
910	openGauss=# CREATE TABLE tpcds.warehouse_t9	950	openGauss=# CREATE TABLE tpcds.warehouse_t9
	@@ -945,8 +985,8 @@ openGauss=# CREATE TABLE tpcds.warehouse_t10
945	);	985	);
946	```	986	```
947		987
948	-```	988	+- 创建一个有主键约束的表。
949	---创建一个有主键约束的表。	989	+```sql
950	openGauss=# CREATE TABLE tpcds.warehouse_t11	990	openGauss=# CREATE TABLE tpcds.warehouse_t11
951	(	991	(
952	W_WAREHOUSE_SK INTEGER PRIMARY KEY,	992	W_WAREHOUSE_SK INTEGER PRIMARY KEY,
	@@ -1024,7 +1064,10 @@ openGauss=# CREATE TABLE tpcds.warehouse_t14
1024	W_GMT_OFFSET DECIMAL(5,2),	1064	W_GMT_OFFSET DECIMAL(5,2),
1025	CONSTRAINT W_CSTR_KEY2 PRIMARY KEY(W_WAREHOUSE_SK, W_WAREHOUSE_ID)	1065	CONSTRAINT W_CSTR_KEY2 PRIMARY KEY(W_WAREHOUSE_SK, W_WAREHOUSE_ID)
1026	);	1066	);
1027	---创建列存表。	1067	+```
		1068	+
		1069	+- 创建列存表。
		1070	+```sql
1028	openGauss=# CREATE TABLE tpcds.warehouse_t15	1071	openGauss=# CREATE TABLE tpcds.warehouse_t15
1029	(	1072	(
1030	W_WAREHOUSE_SK INTEGER NOT NULL,	1073	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -1082,8 +1125,10 @@ openGauss=# CREATE TABLE tpcds.warehouse_t17
1082	W_GMT_OFFSET DECIMAL(5,2)	1125	W_GMT_OFFSET DECIMAL(5,2)
1083	) WITH (ORIENTATION = COLUMN, COMPRESSION=HIGH);	1126	) WITH (ORIENTATION = COLUMN, COMPRESSION=HIGH);
1084		1127
		1128	+```
1085		1129
1086	---定义一个检查列约束。	1130	+- 定义一个检查列约束。
		1131	+```sql
1087	openGauss=# CREATE TABLE tpcds.warehouse_t19	1132	openGauss=# CREATE TABLE tpcds.warehouse_t19
1088	(	1133	(
1089	W_WAREHOUSE_SK INTEGER PRIMARY KEY CHECK (W_WAREHOUSE_SK > 0),	1134	W_WAREHOUSE_SK INTEGER PRIMARY KEY CHECK (W_WAREHOUSE_SK > 0),
	@@ -1121,7 +1166,10 @@ openGauss=# CREATE TABLE tpcds.warehouse_t20
1121	CONSTRAINT W_CONSTR_KEY2 CHECK(W_WAREHOUSE_SK > 0 AND W_WAREHOUSE_NAME IS NOT NULL)	1166	CONSTRAINT W_CONSTR_KEY2 CHECK(W_WAREHOUSE_SK > 0 AND W_WAREHOUSE_NAME IS NOT NULL)
1122	);	1167	);
1123		1168
1124	---创建一个有外键约束的表。	1169	+```
		1170	+
		1171	+- 创建一个有外键约束的表。
		1172	+```sql
1125	openGauss=# CREATE TABLE tpcds.city_t23	1173	openGauss=# CREATE TABLE tpcds.city_t23
1126	(	1174	(
1127	W_CITY VARCHAR(60) PRIMARY KEY,	1175	W_CITY VARCHAR(60) PRIMARY KEY,
	@@ -1185,30 +1233,40 @@ openGauss=# CREATE TABLE tpcds.warehouse_t23
1185	CONSTRAINT W_FORE_KEY1 FOREIGN KEY(W_CITY) REFERENCES tpcds.city_t23(W_CITY)	1233	CONSTRAINT W_FORE_KEY1 FOREIGN KEY(W_CITY) REFERENCES tpcds.city_t23(W_CITY)
1186	);	1234	);
1187		1235
1188	---向tpcds.warehouse_t19表中增加一个varchar列。
1189	```	1236	```
1190		1237
1191	-```	1238	+- 向tpcds.warehouse_t19表中增加一个varchar列。
		1239	+```sql
1192	openGauss=# ALTER TABLE tpcds.warehouse_t19 ADD W_GOODS_CATEGORY varchar(30);	1240	openGauss=# ALTER TABLE tpcds.warehouse_t19 ADD W_GOODS_CATEGORY varchar(30);
1193		1241
1194	---给tpcds.warehouse_t19表增加一个检查约束。	1242	+```
1195	-openGauss=# ALTER TABLE tpcds.warehouse_t19 ADD CONSTRAINT W_CONSTR_KEY4 CHECK (W_STATE IS NOT NULL);
1196		1243
1197	---在一个操作中改变两个现存字段的类型。	1244	+- 给tpcds.warehouse_t19表增加一个检查约束。
		1245	+```sql
		1246	+openGauss=# ALTER TABLE tpcds.warehouse_t19 ADD CONSTRAINT W_CONSTR_KEY4 CHECK (W_STATE IS NOT NULL);
		1247	+```
		1248	+
		1249	+- 在一个操作中改变两个现存字段的类型。
		1250	+```sql
1198	openGauss=# ALTER TABLE tpcds.warehouse_t19	1251	openGauss=# ALTER TABLE tpcds.warehouse_t19
1199	ALTER COLUMN W_GOODS_CATEGORY TYPE varchar(80),	1252	ALTER COLUMN W_GOODS_CATEGORY TYPE varchar(80),
1200	ALTER COLUMN W_STREET_NAME TYPE varchar(100);	1253	ALTER COLUMN W_STREET_NAME TYPE varchar(100);
1201		1254
1202	--此语句与上面语句等效。	1255	--此语句与上面语句等效。
1203	openGauss=# ALTER TABLE tpcds.warehouse_t19 MODIFY (W_GOODS_CATEGORY varchar(30), W_STREET_NAME varchar(60));	1256	openGauss=# ALTER TABLE tpcds.warehouse_t19 MODIFY (W_GOODS_CATEGORY varchar(30), W_STREET_NAME varchar(60));
1204	-	1257	+```
1205	---给一个已存在字段添加非空约束。	1258	+- 给一个已存在字段添加非空约束。
		1259	+```sql
1206	openGauss=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY SET NOT NULL;	1260	openGauss=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY SET NOT NULL;
		1261	+```
1207		1262
1208	---移除已存在字段的非空约束。	1263	+- 移除已存在字段的非空约束。
		1264	+```sql
1209	openGauss=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY DROP NOT NULL;	1265	openGauss=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY DROP NOT NULL;
		1266	+```
1210		1267
1211	---如果列存表中还未指定局部聚簇，向在一个列存表中添加局部聚簇列。	1268	+- 如果列存表中还未指定局部聚簇，向在一个列存表中添加局部聚簇列。
		1269	+```sql
1212	openGauss=# ALTER TABLE tpcds.warehouse_t17 ADD PARTIAL CLUSTER KEY(W_WAREHOUSE_SK);	1270	openGauss=# ALTER TABLE tpcds.warehouse_t17 ADD PARTIAL CLUSTER KEY(W_WAREHOUSE_SK);
1213		1271
1214	--查看约束的名称，并删除一个列存表中的局部聚簇列。	1272	--查看约束的名称，并删除一个列存表中的局部聚簇列。
	@@ -1236,8 +1294,10 @@ Has OIDs: no
1236	Location Nodes: ALL DATANODES	1294	Location Nodes: ALL DATANODES
1237	Options: compression=no, version=0.12	1295	Options: compression=no, version=0.12
1238	openGauss=# ALTER TABLE tpcds.warehouse_t17 DROP CONSTRAINT warehouse_t17_cluster;	1296	openGauss=# ALTER TABLE tpcds.warehouse_t17 DROP CONSTRAINT warehouse_t17_cluster;
		1297	+```
1239		1298
1240	---将表移动到另一个表空间。	1299	+- 将表移动到另一个表空间。
		1300	+```sql
1241	openGauss=# ALTER TABLE tpcds.warehouse_t19 SET TABLESPACE PG_DEFAULT;	1301	openGauss=# ALTER TABLE tpcds.warehouse_t19 SET TABLESPACE PG_DEFAULT;
1242	--创建模式joe。	1302	--创建模式joe。
1243	openGauss=# CREATE SCHEMA joe;	1303	openGauss=# CREATE SCHEMA joe;
	@@ -1248,10 +1308,15 @@ openGauss=# ALTER TABLE tpcds.warehouse_t19 SET SCHEMA joe;
1248	--重命名已存在的表。	1308	--重命名已存在的表。
1249	openGauss=# ALTER TABLE joe.warehouse_t19 RENAME TO warehouse_t23;	1309	openGauss=# ALTER TABLE joe.warehouse_t19 RENAME TO warehouse_t23;
1250		1310
1251	---从warehouse_t23表中删除一个字段。	1311	+```
1252	-openGauss=# ALTER TABLE joe.warehouse_t23 DROP COLUMN W_STREET_NAME;
1253		1312
1254	---创建带INVISIBLE唯一索引的表，需要在B兼容性数据库下	1313	+- 从warehouse_t23表中删除一个字段。
		1314	+```sql
		1315	+openGauss=# ALTER TABLE joe.warehouse_t23 DROP COLUMN W_STREET_NAME;
		1316	+```
		1317	+
		1318	+- 创建带INVISIBLE唯一索引的表，需要在B兼容性数据库下
		1319	+```sql
1255	openGauss=# CREATE TABLE tpcds.warehouse_t26	1320	openGauss=# CREATE TABLE tpcds.warehouse_t26
1256	(	1321	(
1257	W_WAREHOUSE_SK INTEGER NOT NULL,	1322	W_WAREHOUSE_SK INTEGER NOT NULL,
	@@ -1301,6 +1366,62 @@ openGauss=# DROP TABLESPACE DS_TABLESPACE1;
1301	openGauss=# DROP SCHEMA IF EXISTS joe CASCADE;	1366	openGauss=# DROP SCHEMA IF EXISTS joe CASCADE;
1302	```	1367	```
1303		1368
		1369	+- 创建identity列
		1370	+```sql
		1371	+openGauss=# create table t1 (a int generated always as identity, b int);
		1372	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq" for serial column "t1.a"
		1373	+CREATE TABLE
		1374	+openGauss=# \d+ t1
		1375	+ Table "public.t1"
		1376	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		1377	+--------+---------+---------------------------------------+---------+--------------+-------------
		1378	+ a \| integer \| not null generated always as identity \| plain \| \|
		1379	+ b \| integer \| \| plain \| \|
		1380	+Has OIDs: no
		1381	+Options: orientation=row, compression=no
		1382	+
		1383	+openGauss=# create table t2 (a int generated by default as identity, b int);
		1384	+NOTICE: CREATE TABLE will create implicit sequence "t2_a_seq" for serial column "t2.a"
		1385	+CREATE TABLE
		1386	+openGauss=# \d+ t2
		1387	+ Table "public.t2"
		1388	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		1389	+--------+---------+-------------------------------------------+---------+--------------+-------------
		1390	+ a \| integer \| not null generated by default as identity \| plain \| \|
		1391	+ b \| integer \| \| plain \| \|
		1392	+Has OIDs: no
		1393	+Options: orientation=row, compression=no
		1394	+
		1395	+```
		1396	+
		1397	+- create table like (including identity)
		1398	+```sql
		1399	+openGauss=# create table t2_1 (like t2);
		1400	+CREATE TABLE
		1401	+openGauss=# \d+ t2_1
		1402	+ Table "public.t2_1"
		1403	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		1404	+--------+---------+-----------+---------+--------------+-------------
		1405	+ a \| integer \| not null \| plain \| \|
		1406	+ b \| integer \| \| plain \| \|
		1407	+Has OIDs: no
		1408	+Options: orientation=row, compression=no
		1409	+
		1410	+openGauss=# create table t2_2 (like t2 including identity);
		1411	+NOTICE: CREATE TABLE will create implicit sequence "t2_2_a_seq" for serial column "t2_2.a"
		1412	+CREATE TABLE
		1413	+openGauss=# \d+ t2_2
		1414	+ Table "public.t2_2"
		1415	+ Column \| Type \| Modifiers \| Storage \| Stats target \| Description
		1416	+--------+---------+-------------------------------------------+---------+--------------+-------------
		1417	+ a \| integer \| not null generated by default as identity \| plain \| \|
		1418	+ b \| integer \| \| plain \| \|
		1419	+Has OIDs: no
		1420	+Options: orientation=row, compression=no
		1421	+
		1422	+```
		1423	+
		1424	+
1304	## 相关链接<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_scd5caca899f849f697cb50d76c49de4c"></a>	1425	## 相关链接<a name="zh-cn_topic_0283137629_zh-cn_topic_0237122117_zh-cn_topic_0059778169_scd5caca899f849f697cb50d76c49de4c"></a>
1305		1426
1306	[ALTER TABLE](alter_table.md)，[DROP TABLE](drop_table.md)，[CREATE TABLESPACE](create_tablespace.md)	1427	[ALTER TABLE](alter_table.md)，[DROP TABLE](drop_table.md)，[CREATE TABLESPACE](create_tablespace.md)

Mdocs/zh/sql_reference/insert.md+34-2

	@@ -30,8 +30,9 @@
30	INSERT [/+ plan_hint /] INTO	30	INSERT [/+ plan_hint /] INTO
31	{ table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]	31	{ table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]
32	\| ( target_query [ WITH [ CASCADED \| LOCAL ] CHECK OPTION ] ) [ AS ] alias [ ( column_name [, ...] ) ] }	32	\| ( target_query [ WITH [ CASCADED \| LOCAL ] CHECK OPTION ] ) [ AS ] alias [ ( column_name [, ...] ) ] }
		33	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
33	{ DEFAULT VALUES	34	{ DEFAULT VALUES
34	- \| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]	35	+ \| VALUES { ( { expression \| DEFAULT } [, ...] ) } [, ...]
35	\| query }	36	\| query }
36	[ ON DUPLICATE KEY UPDATE { NOTHING \| { column_name = { expression \| DEFAULT } } [, ...] [ WHERE condition ] }]	37	[ ON DUPLICATE KEY UPDATE { NOTHING \| { column_name = { expression \| DEFAULT } } [, ...] [ WHERE condition ] }]
37	[ ON CONFLICT [ conflict_target ] conflict_action ]	38	[ ON CONFLICT [ conflict_target ] conflict_action ]
	@@ -98,7 +99,7 @@ INSERT [/+ plan_hint /] INTO
98	作为插入目标的子查询，相当于视图，仅在参数sql\_compatibility=A时生效。插入限制详见[CREATE VIEW](create_view.md)中可自动更新视图一节。	99	作为插入目标的子查询，相当于视图，仅在参数sql\_compatibility=A时生效。插入限制详见[CREATE VIEW](create_view.md)中可自动更新视图一节。
99		100
100	- WITH [ CASCADED \| LOCAL ] CHECK OPTION	101	- WITH [ CASCADED \| LOCAL ] CHECK OPTION
101	-	102	+
102	详见[CREATE VIEW](create_view.md)一节介绍。	103	详见[CREATE VIEW](create_view.md)一节介绍。
103		104
104	- column\_name	105	- column\_name
	@@ -113,6 +114,12 @@ INSERT [/+ plan_hint /] INTO
113		114
114	取值范围：已存在的字段名。	115	取值范围：已存在的字段名。
115		116
		117	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		118	+
		119	+ 该子句用于插入identity列时的行为控制。
		120	+
		121	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		122	+
116	- expression	123	- expression
117		124
118	赋予对应column的一个有效表达式或值：	125	赋予对应column的一个有效表达式或值：
	@@ -252,6 +259,8 @@ INSERT [/+ plan_hint /] INTO
252		259
253	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>	260	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>
254		261
		262	+- insert语句基础示例
		263	+
255	```sql	264	```sql
256	--创建表tpcds.reason_t2。	265	--创建表tpcds.reason_t2。
257	openGauss=# CREATE TABLE tpcds.reason_t2	266	openGauss=# CREATE TABLE tpcds.reason_t2
	@@ -411,3 +420,26 @@ UPDATE SET email = EXCLUDED.email;
411	INSERT INTO users (id, email, name)	420	INSERT INTO users (id, email, name)
412	VALUES (7, 'frank@example.com', 'Frank') ON CONFLICT (email text_pattern_ops) DO NOTHING;	421	VALUES (7, 'frank@example.com', 'Frank') ON CONFLICT (email text_pattern_ops) DO NOTHING;
413	```	422	```
		423	+
		424	+- OVERRIDING 子句示例
		425	+```sql
		426	+openGauss=# create table t1 (a int generated always as identity, b int);
		427	+NOTICE: CREATE TABLE will create implicit sequence "t1_a_seq" for serial column "t1.a"
		428	+CREATE TABLE
		429	+openGauss=# insert into t1(a, b) values(1, 1);
		430	+ERROR: cannot insert a non-DEFAULT value into column "a"
		431	+DETAIL: Column "a" is an identity column defined as "GENERATED ALWAYS".
		432	+HINT: Use OVERRIDING SYSTEM VALUE to override.
		433	+openGauss=# insert into t1(a, b) OVERRIDING SYSTEM VALUE values(10, 1);
		434	+INSERT 0 1
		435	+openGauss=# insert into t1(a, b) OVERRIDING USER VALUE values(10, 1);
		436	+INSERT 0 1
		437	+openGauss=# select * from t1 order by a, b;
		438	+ a \| b
		439	+----+---
		440	+ 1 \| 1
		441	+ 2 \| 1
		442	+ 10 \| 1
		443	+(3 rows)
		444	+
		445	+```

Mdocs/zh/sql_reference/merge_into.md+65-3

	@@ -22,8 +22,9 @@ ON ( condition )
22	]	22	]
23	[	23	[
24	WHEN NOT MATCHED THEN	24	WHEN NOT MATCHED THEN
25	- INSERT { DEFAULT VALUES \|	25	+ INSERT [ ( column_name [, ...] ) ]
26	- [ ( column_name [, ...] ) ] VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }	26	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
		27	+ { DEFAULT VALUES \| VALUES ( { expression \| subquery \| DEFAULT } [, ...] ) [, ...] [ WHERE condition ] }
27	];	28	];
28	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!	29	NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRALIZED mode!
29	```	30	```
	@@ -91,6 +92,12 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
91		92
92	WHEN MATCHED和WHEN NOT MATCHED子句顺序可以交换，可以缺省其中一个，但不能同时缺省，不支持同时指定两个WHEN MATCHED或WHEN NOT MATCHED子句。	93	WHEN MATCHED和WHEN NOT MATCHED子句顺序可以交换，可以缺省其中一个，但不能同时缺省，不支持同时指定两个WHEN MATCHED或WHEN NOT MATCHED子句。
93		94
		95	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		96	+
		97	+ 该子句用于插入identity列时的行为控制。
		98	+
		99	+ `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		100	+
94	- DEFAULT	101	- DEFAULT
95		102
96	用对应字段的缺省值填充该字段。	103	用对应字段的缺省值填充该字段。
	@@ -103,7 +110,8 @@ NOTICE: 'subquery' in the UPDATE and INSERT clauses are only avaliable in CENTRA
103		110
104	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>	111	## 示例<a name="zh-cn_topic_0283137308_zh-cn_topic_0237122170_section3650125620712"></a>
105		112
106	-```	113	+- merge into语句基础示例
		114	+```sql
107	-- 创建目标表products和源表newproducts，并插入数据	115	-- 创建目标表products和源表newproducts，并插入数据
108	openGauss=# CREATE TABLE products	116	openGauss=# CREATE TABLE products
109	(	117	(
	@@ -156,3 +164,57 @@ openGauss=# SELECT * FROM products ORDER BY product_id;
156	openGauss=# DROP TABLE products;	164	openGauss=# DROP TABLE products;
157	openGauss=# DROP TABLE newproducts;	165	openGauss=# DROP TABLE newproducts;
158	```	166	```
		167	+
		168	+- merge into when not matched then insert overriding clause示例
		169	+```sql
		170	+openGauss=# create table target_table (
		171	+openGauss(# id int GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
		172	+openGauss(# name varchar(50),
		173	+openGauss(# age int
		174	+openGauss(# );
		175	+NOTICE: CREATE TABLE will create implicit sequence "target_table_id_seq" for serial column "target_table.id"
		176	+NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "target_table_pkey" for table "target_table"
		177	+CREATE TABLE
		178	+openGauss=# create table source_table (id int, name varchar(50), age int);
		179	+CREATE TABLE
		180	+openGauss=# insert into source_table values (10, 'zliu', 28), (11, 'sqi', 30);
		181	+INSERT 0 2
		182	+openGauss=# -- expected: success. let id generated by system.
		183	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		184	+openGauss-# when not matched then
		185	+openGauss-# insert (name, age) values (s.name, s.age);
		186	+MERGE 2
		187	+openGauss=# -- expected: error
		188	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		189	+openGauss-# when not matched then
		190	+openGauss-# insert (id, name, age) values (1, 'error', 21);
		191	+ERROR: cannot insert a non-DEFAULT value into column "id"
		192	+DETAIL: Column "id" is an identity column defined as "GENERATED ALWAYS".
		193	+HINT: Use OVERRIDING SYSTEM VALUE to override
		194	+openGauss=# -- expected: success
		195	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		196	+openGauss-# when not matched then
		197	+openGauss-# insert (id, name, age) OVERRIDING USER VALUE values (1, 'success', 22); -- 3
		198	+MERGE 2
		199	+openGauss=# -- expected: error
		200	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		201	+openGauss-# when not matched then
		202	+openGauss-# insert (id, name, age) OVERRIDING SYSTEM VALUE values (2, 'error', 23);
		203	+ERROR: duplicate key value violates unique constraint "target_table_pkey"
		204	+DETAIL: Key (id)=(2) already exists.
		205	+openGauss=# -- expected: error
		206	+openGauss=# merge into target_table AS t using source_table AS s ON t.id = s.id
		207	+openGauss-# when not matched then
		208	+openGauss-# insert (id, name, age) OVERRIDING SYSTEM VALUE values (3, 'error', 24);
		209	+ERROR: duplicate key value violates unique constraint "target_table_pkey"
		210	+DETAIL: Key (id)=(3) already exists.
		211	+openGauss=# select * from target_table order by 1,2,3;
		212	+ id \| name \| age
		213	+----+---------+-----
		214	+ 1 \| zliu \| 28
		215	+ 2 \| sqi \| 30
		216	+ 3 \| success \| 22
		217	+ 4 \| success \| 22
		218	+(4 rows)
		219	+
		220	+```

Mdocs/zh/sql_reference/replace_into.md+26-1

	@@ -16,6 +16,7 @@
16	```	16	```
17	[ WITH [ RECURSIVE ] with_query [, ...] ]	17	[ WITH [ RECURSIVE ] with_query [, ...] ]
18	REPLACE [/+ plan_hint /] INTO table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]	18	REPLACE [/+ plan_hint /] INTO table_name [partition_clause] [ AS alias ] [ ( column_name [, ...] ) ]
		19	+ [ OVERRIDING { SYSTEM \| USER } VALUE ]
19	{ DEFAULT VALUES	20	{ DEFAULT VALUES
20	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]	21	\| VALUES {( { expression \| DEFAULT } [, ...] ) }[, ...]
21	\| query }	22	\| query }
	@@ -80,6 +81,12 @@ NULL。
80		81
81	取值范围：已存在的字段名。	82	取值范围：已存在的字段名。
82		83
		84	+- OVERRIDING \{ SYSTEM \| USER \} VALUE
		ywzq11613277847月29日【问题描述】 create_table.md insert.md replace_into.md 【修改建议】这三个文件在lite版本也加上，保证lite版本和非lite保持一致，顺便改下冲突 XXXCA 7月29日评论： 7月29日评论：
		85	+
		86	+ 该子句用于插入identity列时的行为控制。
		87	+
		88	+ - `OVERRIDING SYSTEM VALUE`用于覆盖identity列生成的系统值，`OVERRIDING USER VALUE`用于覆盖用户自定义值。
		89	+
83	- expression	90	- expression
84		91
85	赋予对应column的一个有效表达式或值。	92	赋予对应column的一个有效表达式或值。
	@@ -118,7 +125,9 @@ NULL。
118		125
119	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>	126	## 示例<a name="zh-cn_topic_0283137542_zh-cn_topic_0237122167_zh-cn_topic_0059778902_sfff14489321642278317cf06cd89810d"></a>
120		127
121	-```	128	+- replace into语句基础示例
		129	+
		130	+```sql
122	-- 创建表test.	131	-- 创建表test.
123	openGauss=# CREATE TABLE test (col1 int PRIMARY KEY, col2 INT);	132	openGauss=# CREATE TABLE test (col1 int PRIMARY KEY, col2 INT);
124		133
	@@ -151,4 +160,20 @@ openGauss=# select * from test;
151	1 \| 5	160	1 \| 5
152	2 \| 6	161	2 \| 6
153	(4 rows)	162	(4 rows)
		163	+```
154		164
		165	+- OVERRIDING clause示例
		166	+```sql
		167	+openGauss=# CREATE TABLE test_t1 (a int GENERATED ALWAYS AS IDENTITY, b text, c int);
		168	+NOTICE: CREATE TABLE will create implicit sequence "test_t1_a_seq" for serial column "test_t1.a"
		169	+CREATE TABLE
		170	+openGauss=# REPLACE INTO test_t1 (a, b, c) VALUES (1, 'alice', 25); -- error
		171	+ERROR: cannot insert a non-DEFAULT value into column "a"
		172	+DETAIL: Column "a" is an identity column defined as "GENERATED ALWAYS".
		173	+HINT: Use OVERRIDING SYSTEM VALUE to override.
		174	+openGauss=# -- error REPLACE can not work on sequence!
		175	+openGauss=# REPLACE INTO test_t1 (a, b, c) OVERRIDING SYSTEM VALUE VALUES (1, 'alice', 25);
		176	+ERROR: REPLACE can not work on sequence!
		177	+openGauss=#
		178	+
		179	+```