*
* view.cpp
* use rewrite rules to construct views
*
* Portions Copyright (c) 2020 Huawei Technologies Co.,Ltd.
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/gausskernel/optimizer/commands/view.cpp
*
* -------------------------------------------------------------------------
*/
#include "postgres.h"
#include "knl/knl_variable.h"
#include "access/heapam.h"
#include "access/xact.h"
#include "catalog/gs_matview.h"
#include "catalog/gs_matview_dependency.h"
#include "catalog/namespace.h"
#include "catalog/gs_column_keys.h"
#include "catalog/gs_encrypted_columns.h"
#include "client_logic/cache.h"
#include "commands/defrem.h"
#include "commands/tablecmds.h"
#include "commands/view.h"
#include "miscadmin.h"
#include "gs_policy/policy_common.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "parser/analyze.h"
#include "parser/parse_relation.h"
#include "parser/parsetree.h"
#include "rewrite/rewriteDefine.h"
#include "rewrite/rewriteManip.h"
#include "rewrite/rewriteHandler.h"
#include "rewrite/rewriteSupport.h"
#include "optimizer/nodegroups.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/rel_gs.h"
#include "utils/syscache.h"
#include "foreign/foreign.h"
#include "parser/parse_type.h"
#ifdef PGXC
#include "pgxc/execRemote.h"
#include "tcop/utility.h"
#endif
static void checkViewTupleDesc(TupleDesc newdesc, TupleDesc olddesc);
InSideView query_from_view_hook = NULL;
* Validator for "check_option" reloption on views. The allowed values
* are "local" and "cascaded".
*/
void validateWithCheckOption(const char *value)
{
if (value == NULL || (pg_strcasecmp(value, "local") != 0 && pg_strcasecmp(value, "cascaded") != 0)) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid value for \"check_option\" option"),
errdetail("Valid values are \"local\", and \"cascaded\".")));
}
}
* Validator for "view_sql_security" reloption on views. The allowed values
* are "local" and "cascaded".
*/
void validateViewSecurityOption(const char *value)
{
if (value == NULL || (pg_strcasecmp(value, "definer") != 0 && pg_strcasecmp(value, "invoker") != 0)) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid value for \"view_sql_security\" option"),
errdetail("Valid values are \"INVOKER\", and \"DEFINER\".")));
}
}
static void setEncryptedColumnRef(ColumnDef *def, TargetEntry *tle)
{
def->clientLogicColumnRef = (ClientLogicColumnRef*)palloc(sizeof(ClientLogicColumnRef));
HeapTuple tup = SearchSysCache2(CERELIDCOUMNNAME, ObjectIdGetDatum(tle->resorigtbl), CStringGetDatum(def->colname));
if (!HeapTupleIsValid(tup)) {
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN), errmsg("client encrypted column \"%s\" does not exist", def->colname)));
}
Form_gs_encrypted_columns ce_form = (Form_gs_encrypted_columns) GETSTRUCT(tup);
HeapTuple setting_tup = SearchSysCache1(COLUMNSETTINGOID, ObjectIdGetDatum(ce_form->column_key_id));
if (!HeapTupleIsValid(setting_tup)) {
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("client encrypted column key %u does not exist", ce_form->column_key_id)));
}
Form_gs_column_keys setting_form = (Form_gs_column_keys) GETSTRUCT(setting_tup);
def->clientLogicColumnRef->column_key_name = list_make1(makeString(NameStr(setting_form->column_key_name)));
ReleaseSysCache(setting_tup);
ReleaseSysCache(tup);
def->clientLogicColumnRef->orig_typname =
makeTypeNameFromOid(exprTypmod((Node*)tle->expr), -1);
def->clientLogicColumnRef->dest_typname =
makeTypeNameFromOid(exprType((Node*)tle->expr), exprTypmod((Node*)tle->expr));
}
* DefineVirtualRelation
*
* Create a view relation and use the rules system to store the query
* for the view.
* ---------------------------------------------------------------------
*/
static ObjectAddress DefineVirtualRelation(RangeVar* relation, List* tlist, bool replace, List* options, ObjectType relkind,
ViewStmt* stmt, Query* viewParse)
{
Oid viewOid;
LOCKMODE lockmode;
CreateStmt* createStmt = makeNode(CreateStmt);
List* attrList = NIL;
ListCell* t = NULL;
char* definer = stmt->definer;
bool is_alter = stmt->is_alter;
* create a list of ColumnDef nodes based on the names and types of the
* (non-junk) targetlist items from the view's SELECT list.
*/
foreach (t, tlist) {
TargetEntry* tle = (TargetEntry*)lfirst(t);
if (!tle->resjunk) {
ColumnDef* def = makeNode(ColumnDef);
def->colname = pstrdup(tle->resname);
def->typname = makeTypeNameFromOid(exprType((Node*)tle->expr), exprTypmod((Node*)tle->expr));
def->inhcount = 0;
def->is_local = true;
def->is_not_null = false;
def->is_from_type = false;
def->storage = 0;
def->cmprs_mode = ATT_CMPR_NOCOMPRESS;
def->raw_default = NULL;
def->update_default = NULL;
def->cooked_default = NULL;
def->collClause = NULL;
def->collOid = exprCollation((Node*)tle->expr);
if IsClientLogicType(exprType((Node*)tle->expr)) {
setEncryptedColumnRef(def, tle);
}
* It's possible that the column is of a collatable type but the
* collation could not be resolved, so double-check.
*/
if (type_is_collatable(exprType((Node*)tle->expr))) {
if (!OidIsValid(def->collOid))
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_COLLATION),
errmsg("could not determine which collation to use for view column \"%s\"", def->colname),
errhint("Use the COLLATE clause to set the collation explicitly.")));
} else if (!(DB_IS_CMPT(B_FORMAT) && ENABLE_MULTI_CHARSET && IsBinaryType(exprType((Node*)tle->expr)))) {
Assert(!OidIsValid(def->collOid));
}
def->constraints = NIL;
attrList = lappend(attrList, def);
}
}
if (attrList == NIL)
ereport(ERROR, (errcode(ERRCODE_INVALID_TABLE_DEFINITION), errmsg("view must have at least one column")));
* Look up, check permissions on, and lock the creation namespace; also
* check for a preexisting view with the same name. This will also set
* relation->relpersistence to RELPERSISTENCE_TEMP if the selected
* namespace is temporary.
*/
lockmode = replace ? AccessExclusiveLock : NoLock;
(void)RangeVarGetAndCheckCreationNamespace(relation, lockmode, &viewOid, RELKIND_VIEW);
if (!OidIsValid(viewOid) && is_alter) {
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_TABLE), errmsg("view \"%s\" does not exist", relation->relname)));
}
bool flag = OidIsValid(viewOid) && replace;
if (flag) {
Relation rel;
TupleDesc descriptor;
List* atcmds = NIL;
AlterTableCmd* atcmd = NULL;
ObjectAddress address;
* During inplace upgrade, if we are doing rolling back, the old-versioned
* relcache would cause problems. So update them anyway.
*/
if (u_sess->attr.attr_common.IsInplaceUpgrade)
RelationCacheInvalidateEntry(viewOid);
rel = relation_open(viewOid, NoLock);
flag = rel->rd_rel->relkind != RELKIND_VIEW && rel->rd_rel->relkind != RELKIND_CONTQUERY;
if (flag)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("\"%s\" is not a view", RelationGetRelationName(rel))));
CheckTableNotInUse(rel, "CREATE OR REPLACE VIEW");
* Due to the namespace visibility rules for temporary objects, we
* should only end up replacing a temporary view with another
* temporary view, and similarly for permanent views.
*/
Assert(relation->relpersistence == rel->rd_rel->relpersistence);
* Create a tuple descriptor to compare against the existing view, and
* verify that the old column list is an initial prefix of the new
* column list.
*/
descriptor = BuildDescForRelation(attrList, (Node*)makeString(ORIENTATION_ROW));
* During inplace or online upgrade, we may need to drop newly-added
* view columns to perform rollback. Since these columns should have
* not been visible to users, we just skip the safety check.
*/
if (!u_sess->attr.attr_common.IsInplaceUpgrade) {
PG_TRY();
{
checkViewTupleDesc(descriptor, rel->rd_att);
}
PG_CATCH();
{
relation_close(rel, NoLock);
PG_RE_THROW();
}
PG_END_TRY();
}
* set definer by AlterTameCmd
*/
if (definer != NULL) {
Oid ownerOid = get_role_oid(definer, false);
bool isOwnerChange = false;
if (!OidIsValid(ownerOid)) {
ownerOid = GetUserId();
} else if (ownerOid != GetUserId()) {
isOwnerChange = true;
}
if (isOwnerChange && !is_alter) {
AclResult aclresult;
Oid namespaceId = RangeVarGetAndCheckCreationNamespace(relation, NoLock, NULL, relkind);
aclresult = pg_namespace_aclcheck(namespaceId, ownerOid, ACL_CREATE);
bool anyResult = false;
if (aclresult != ACLCHECK_OK && !IsSysSchema(namespaceId)) {
anyResult = CheckRelationCreateAnyPrivilege(ownerOid, relkind);
}
if (aclresult != ACLCHECK_OK && !anyResult) {
aclcheck_error(aclresult, ACL_KIND_NAMESPACE, get_namespace_name(namespaceId));
}
}
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_ChangeOwner;
atcmd->name = definer;
atcmds = lappend(atcmds, atcmd);
}
* If new attributes have been added, we must add pg_attribute entries
* for them. It is convenient (although overkill) to use the ALTER
* TABLE ADD COLUMN infrastructure for this.
*
* When we roll back upgrade by dropping view columns, we use the
* ALTER TABLE DROP COLUMN infrastructure.
*/
flag = (list_length(attrList) < rel->rd_att->natts) && u_sess->attr.attr_common.IsInplaceUpgrade;
if (list_length(attrList) > rel->rd_att->natts) {
ListCell* c = NULL;
int skip = rel->rd_att->natts;
foreach (c, attrList) {
if (skip > 0) {
skip--;
continue;
}
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_AddColumnToView;
atcmd->def = (Node*)lfirst(c);
atcmds = lappend(atcmds, atcmd);
}
} else if (flag) {
for (int dropcolno = rel->rd_att->natts - 1; dropcolno >= list_length(attrList); dropcolno--) {
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_DropColumn;
atcmd->name = rel->rd_att->attrs[dropcolno].attname.data;
atcmd->behavior = DROP_RESTRICT;
atcmd->missing_ok = true;
atcmds = lappend(atcmds, atcmd);
}
}
if (atcmds) {
AlterTableInternal(viewOid, atcmds, true);
CommandCounterIncrement();
}
* Update the query for the view.
*
* Note that we must do this before updating the view options, because
* the new options may not be compatible with the old view query (for
* example if we attempt to add the WITH CHECK OPTION, we require that
* the new view be automatically updatable, but the old view may not
* have been).
*/
StoreViewQuery(viewOid, viewParse, replace);
CommandCounterIncrement();
* Finally update the view options.
*
* The new options list replaces the existing options list, even if
* it's empty.
*/
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_ReplaceRelOptions;
atcmd->def = (Node*)options;
atcmds = list_make1(atcmd);
AlterTableInternal(viewOid, atcmds, true);
* There is very little to do here to update the view's dependencies.
* Most view-level dependency relationships, such as those on the
* owner, schema, and associated composite type, aren't changing.
* Because we don't allow changing type or collation of an existing
* view column, those dependencies of the existing columns don't
* change either, while the AT_AddColumnToView machinery took care of
* adding such dependencies for new view columns. The dependencies of
* the view's query could have changed arbitrarily, but that was dealt
* with inside StoreViewQuery. What remains is only to check that
* view replacement is allowed when we're creating an extension.
*/
ObjectAddressSet(address, RelationRelationId, viewOid);
recordDependencyOnCurrentExtension(&address, true);
* Seems okay, so return the OID of the pre-existing view.
*/
relation_close(rel, NoLock);
return address;
} else {
ObjectAddress address;
* now set the parameters for keys/inheritance etc. All of these are
* uninteresting for views...
*/
createStmt->relation = relation;
createStmt->tableElts = attrList;
createStmt->inhRelations = NIL;
createStmt->constraints = NIL;
createStmt->options = options;
createStmt->options = lappend(options, defWithOids(false));
createStmt->oncommit = ONCOMMIT_NOOP;
createStmt->tablespacename = NULL;
createStmt->if_not_exists = false;
createStmt->charset = PG_INVALID_ENCODING;
Oid ownerOid = InvalidOid;
* get oid by user name
*/
if (definer != NULL) {
ownerOid = get_role_oid(definer, false);
}
* finally create the relation (this will error out if there's an
* existing view, so we don't need more code to complain if "replace"
* is false).
*/
if (relkind == OBJECT_CONTQUERY) {
address = DefineRelation(createStmt, RELKIND_CONTQUERY, ownerOid, NULL);
} else {
address = DefineRelation(createStmt, RELKIND_VIEW, ownerOid, NULL);
}
Assert(address.objectId != InvalidOid);
CommandCounterIncrement();
StoreViewQuery(address.objectId, viewParse, replace);
return address;
}
}
* Verify that tupledesc associated with proposed new view definition
* matches tupledesc of old view. This is basically a cut-down version
* of equalTupleDescs(), with code added to generate specific complaints.
* Also, we allow the new tupledesc to have more columns than the old.
*/
static void checkViewTupleDesc(TupleDesc newdesc, TupleDesc olddesc)
{
int i;
if (newdesc->natts < olddesc->natts)
ereport(ERROR, (errcode(ERRCODE_INVALID_TABLE_DEFINITION), errmsg("cannot drop columns from view")));
for (i = 0; i < olddesc->natts; i++) {
Form_pg_attribute newattr = &newdesc->attrs[i];
Form_pg_attribute oldattr = &olddesc->attrs[i];
if (newattr->attisdropped != oldattr->attisdropped)
ereport(ERROR, (errcode(ERRCODE_INVALID_TABLE_DEFINITION), errmsg("cannot drop columns from view")));
if (strcmp(NameStr(newattr->attname), NameStr(oldattr->attname)) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot change name of view column \"%s\" to \"%s\"",
NameStr(oldattr->attname),
NameStr(newattr->attname))));
if (newattr->atttypid != oldattr->atttypid || newattr->atttypmod != oldattr->atttypmod)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot change data type of view column \"%s\" from %s to %s",
NameStr(oldattr->attname),
format_type_with_typemod(oldattr->atttypid, oldattr->atttypmod),
format_type_with_typemod(newattr->atttypid, newattr->atttypmod))));
}
* We ignore the constraint fields. The new view desc can't have any
* constraints, and the only ones that could be on the old view are
* defaults, which we are happy to leave in place.
*/
}
static void DefineViewRules(Oid viewOid, Query* viewParse, bool replace)
{
* Set up the ON SELECT rule. Since the query has already been through
* parse analysis, we use DefineQueryRewrite() directly.
*/
DefineQueryRewrite(pstrdup(ViewSelectRuleName), viewOid, NULL, CMD_SELECT, true, replace, list_make1(viewParse));
* Someday: automatic ON INSERT, etc
*/
}
* UpdateRangeTableOfViewParse
*
* Update the range table of the given parsetree.
* This update consists of adding two new entries IN THE BEGINNING
* of the range table (otherwise the rule system will die a slow,
* horrible and painful death, and we do not want that now, do we?)
* one for the OLD relation and one for the NEW one (both of
* them refer in fact to the "view" relation).
*
* Of course we must also increase the 'varnos' of all the Var nodes
* by 2...
*
* These extra RT entries are not actually used in the query,
* except for run-time permission checking.
* ---------------------------------------------------------------
*/
Query* UpdateRangeTableOfViewParse(Oid viewOid, Query* viewParse)
{
Relation viewRel;
List* new_rt = NIL;
RangeTblEntry *rt_entry1, *rt_entry2;
* Make a copy of the given parsetree. It's not so much that we don't
* want to scribble on our input, it's that the parser has a bad habit of
* outputting multiple links to the same subtree for constructs like
* BETWEEN, and we mustn't have OffsetVarNodes increment the varno of a
* Var node twice. copyObject will expand any multiply-referenced subtree
* into multiple copies.
*/
viewParse = (Query*)copyObject(viewParse);
viewRel = relation_open(viewOid, AccessShareLock);
* Create the 2 new range table entries and form the new range table...
* OLD first, then NEW....
*/
rt_entry1 = addRangeTableEntryForRelation(NULL, viewRel, makeAlias("old", NIL), false, false);
rt_entry2 = addRangeTableEntryForRelation(NULL, viewRel, makeAlias("new", NIL), false, false);
rt_entry1->requiredPerms = 0;
rt_entry2->requiredPerms = 0;
new_rt = lcons(rt_entry1, lcons(rt_entry2, viewParse->rtable));
viewParse->rtable = new_rt;
* Now offset all var nodes by 2, and jointree RT indexes too.
*/
OffsetVarNodes((Node*)viewParse, 2, 0);
relation_close(viewRel, AccessShareLock);
return viewParse;
}
#ifdef ENABLE_MULTIPLE_NODES
static void CreateMvCommand(ViewStmt* stmt, const char* queryString)
{
Oid groupid = 0;
char* queryStringinfo = (char*)queryString;
char* group_name = NULL;
if (stmt->subcluster == NULL) {
group_name = ng_get_installation_group_name();
} else {
group_name = strVal(linitial(stmt->subcluster->members));
}
groupid = get_pgxc_groupoid(group_name);
if (!OidIsValid(groupid)) {
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("Target node group \"%s\" doesn't exist", group_name)));
}
RemoteQuery* step = makeNode(RemoteQuery);
step->combine_type = COMBINE_TYPE_NONE;
step->sql_statement = (char*)queryString;
step->exec_type = EXEC_ON_DATANODES;
step->is_temp = false;
step->exec_nodes = makeNode(ExecNodes);
step->exec_nodes->distribution.group_oid = groupid;
Oid* members = NULL;
int nmembers = 0;
nmembers = get_pgxc_groupmembers(groupid, &members);
step->exec_nodes->nodeList = GetNodeGroupNodeList(members, nmembers);
pfree_ext(members);
processutility_context proutility_cxt;
proutility_cxt.parse_tree = (Node*)step;
proutility_cxt.query_string = queryStringinfo;
proutility_cxt.readOnlyTree = false;
proutility_cxt.params = NULL;
proutility_cxt.is_top_level = false;
ProcessUtility(&proutility_cxt,
None_Receiver,
true,
NULL);
return;
}
#endif
* Check the base relation of view whether is a MySQL foreign table
* for WITH CHECK OPTION.
*
* Return true if it is, false means that it isn't or the view could not
* be auto-updatable.
*/
bool CheckMySQLFdwForWCO(Query* viewquery)
{
RangeTblRef* rtr = NULL;
if (list_length(viewquery->jointree->fromlist) != 1) {
return false;
}
rtr = (RangeTblRef*)linitial(viewquery->jointree->fromlist);
if (!IsA(rtr, RangeTblRef)) {
return false;
}
RangeTblEntry* base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
if (base_rte->relkind == RELKIND_FOREIGN_TABLE) {
return isMysqlFDWFromTblOid(base_rte->relid);
} else if (base_rte->relkind == RELKIND_VIEW) {
Relation base_rel = try_relation_open(base_rte->relid, AccessShareLock);
bool res = CheckMySQLFdwForWCO(get_view_query(base_rel));
relation_close(base_rel, AccessShareLock);
return res;
}
return false;
}
* DefineView
* Execute a CREATE VIEW command.
*/
ObjectAddress DefineView(ViewStmt* stmt, const char* queryString, bool send_remote, bool isFirstNode)
{
Query* viewParse = NULL;
RangeVar* view = NULL;
ListCell* cell = NULL;
bool check_option;
ObjectAddress address;
* Run parse analysis to convert the raw parse tree to a Query. Note this
* also acquires sufficient locks on the source table(s).
*/
if (!IsA(stmt->query, Query)) {
viewParse = parse_analyze(stmt->query, queryString, NULL, 0);
} else {
viewParse = (Query *)stmt->query;
}
if (viewParse->has_uservar && IsA(stmt->query, SelectStmt)) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("View's SELECT contains a variable or parameter")));
}
* The grammar should ensure that the result is a single SELECT Query.
* However, it doesn't forbid SELECT INTO, so we have to check for that.
*/
if (!IsA(viewParse, Query)) {
ereport(ERROR, (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), errmsg("unexpected parse analysis result")));
}
if (viewParse->utilityStmt != NULL && IsA(viewParse->utilityStmt, CreateTableAsStmt)) {
ereport(
ERROR, (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), errmsg("views must not contain SELECT INTO")));
}
if (viewParse->commandType != CMD_SELECT || viewParse->utilityStmt != NULL) {
ereport(ERROR, (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), errmsg("unexpected parse analysis result")));
}
* Check for unsupported cases. These tests are redundant with ones in
* DefineQueryRewrite(), but that function will complain about a bogus ON
* SELECT rule, and we'd rather the message complain about a view.
*/
if (viewParse->hasModifyingCTE) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("views must not contain data-modifying statements in WITH")));
}
#ifdef ENABLE_MULTIPLE_NODES
validate_streaming_engine_status((Node*) stmt);
#endif
* If the user specified the WITH CHECK OPTION, add it to the list of
* reloptions.
*/
if (stmt->withCheckOption == LOCAL_CHECK_OPTION)
stmt->options = lappend(stmt->options, makeDefElem("check_option", (Node*)makeString("local")));
else if (stmt->withCheckOption == CASCADED_CHECK_OPTION)
stmt->options = lappend(stmt->options, makeDefElem("check_option", (Node*)makeString("cascaded")));
* For B format sql security option ,add it to the list of reloptions.
*/
if (stmt->viewSecurityOption == VIEW_SQL_SECURITY_DEFINER)
stmt->options = lappend(stmt->options, makeDefElem("view_sql_security", (Node*)makeString("definer")));
else if (stmt->viewSecurityOption == VIEW_SQL_SECURITY_INVOKER)
stmt->options = lappend(stmt->options, makeDefElem("view_sql_security", (Node*)makeString("invoker")));
* Check that the view is auto-updatable if WITH CHECK OPTION was
* specified.
*/
check_option = false;
foreach(cell, stmt->options) {
DefElem* defel = (DefElem*)lfirst(cell);
if (pg_strcasecmp(defel->defname, "check_option") == 0)
check_option = true;
}
* If the check option is specified, look to see if the view is
* actually auto-updatable or not.
*/
if (check_option) {
const char *view_updatable_error = view_query_is_auto_updatable(viewParse, true);
if (view_updatable_error)
ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("WITH CHECK OPTION is supported only on auto-updatable views"),
errhint("%s", view_updatable_error)));
* Views based on MySQL foreign table is not allowed to add check option,
* because returning clause which check option dependend on is not supported
* on MySQL.
*/
if (CheckMySQLFdwForWCO(viewParse))
ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("WITH CHECK OPTION is not supported on views that base on MySQL foreign table")));
}
* If a list of column names was given, run through and insert these into
* the actual query tree. - thomas 2000-03-08
*/
if (stmt->aliases != NIL) {
ListCell* alist_item = list_head(stmt->aliases);
ListCell* targetList = NULL;
foreach (targetList, viewParse->targetList) {
TargetEntry* te = (TargetEntry*)lfirst(targetList);
Assert(IsA(te, TargetEntry));
if (te->resjunk)
continue;
te->resname = pstrdup(strVal(lfirst(alist_item)));
alist_item = lnext(alist_item);
if (alist_item == NULL)
break;
}
if (alist_item != NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CREATE VIEW specifies more column "
"names than columns")));
}
if (stmt->view->relpersistence == RELPERSISTENCE_UNLOGGED)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR), errmsg("views cannot be unlogged because they do not have storage")));
if (stmt->view->relpersistence == RELPERSISTENCE_GLOBAL_TEMP) {
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR), errmsg("views cannot be global temp because they do not have storage")));
}
* If the user didn't explicitly ask for a temporary view, check whether
* we need one implicitly. We allow TEMP to be inserted automatically as
* long as the CREATE command is consistent with that --- no explicit
* schema name.
*/
view = (RangeVar*)copyObject(stmt->view);
if (view->relpersistence == RELPERSISTENCE_PERMANENT && isQueryUsingTempRelation(viewParse)) {
view->relpersistence = RELPERSISTENCE_TEMP;
ereport(NOTICE, (errmsg("view \"%s\" will be a temporary view", view->relname)));
}
#ifdef PGXC
if (view->relpersistence == RELPERSISTENCE_TEMP)
ExecSetTempObjectIncluded();
#endif
if (stmt->relkind == OBJECT_MATVIEW) {
Oid viewOid = InvalidOid;
(void)RangeVarGetAndCheckCreationNamespace(view, NoLock, &viewOid, RELKIND_MATVIEW);
ObjectAddressSet(address, RelationRelationId, viewOid);
#ifdef ENABLE_MULTIPLE_NODES
if (IS_PGXC_COORDINATOR && !IsConnFromCoord() && !send_remote) {
CreateMvCommand(stmt, queryString);
}
#endif
StoreViewQuery(viewOid, viewParse, stmt->replace);
} else {
* Create the view relation
*
* NOTE: if it already exists and replace is false, the xact will be
* aborted.
*/
address = DefineVirtualRelation(view, viewParse->targetList, stmt->replace, stmt->options,
stmt->relkind, stmt, viewParse);
* The relation we have just created is not visible to any other commands
* running with the same transaction & command id. So, increment the
* command id counter (but do NOT pfree any memory!!!!)
*/
CommandCounterIncrement();
}
return address;
}
bool IsViewTemp(ViewStmt* stmt, const char* queryString)
{
Query* viewParse = NULL;
RangeVar* view = NULL;
view = (RangeVar*)copyObject(((ViewStmt*)stmt)->view);
viewParse = parse_analyze((Node*)copyObject(((ViewStmt*)stmt)->query), queryString, NULL, 0, false, true);
* If the user didn't explicitly ask for a temporary view, check whether
* we need one implicitly. We allow TEMP to be inserted automatically as
* long as the CREATE command is consistent with that --- no explicit
* schema name.
*/
if (view->relpersistence == RELPERSISTENCE_PERMANENT && isQueryUsingTempRelation(viewParse)) {
view->relpersistence = RELPERSISTENCE_TEMP;
}
if (view->relpersistence == RELPERSISTENCE_TEMP)
return true;
return false;
}
* Use the rules system to store the query for the view.
*/
void
StoreViewQuery(Oid viewOid, Query *viewParse, bool replace)
{
* The range table of 'viewParse' does not contain entries for the "OLD"
* and "NEW" relations. So... add them!
*/
viewParse = UpdateRangeTableOfViewParse(viewOid, viewParse);
* Now create the rules associated with the view.
*/
DefineViewRules(viewOid, viewParse, replace);
}
