PGXC_CLASS
PGXC_CLASS records the replicated or distributed information for each table. The PGXC_CLASS system catalog has specific meanings only in distributed scenarios. openGauss can only query the table definition.
Table 1 PGXC_CLASS columns
Name
|
Type
|
Description
|
|---|
pcrelid
|
oid
|
Table OID
|
pclocatortype
|
"char"
|
Locator type - H: Hash
- G: Range
- L: List
- M: Modulo
- N: Round Robin
- R: Replication
|
pchashalgorithm
|
smallint
|
Distributed tuple using the hash algorithm
|
pchashbuckets
|
smallint
|
Value of a hash container
|
pgroup
|
name
|
Name of the node
|
redistributed
|
"char"
|
Indicates that a table has been redistributed.
|
redis_order
|
integer
|
Redistribution sequence. Tables whose values are 0 will not be redistributed in this round of redistribution.
|
pcattnum
|
int2vector
|
Column number used as a distributed key
|
nodeoids
|
oidvector_extend
|
List of distributed table node OIDs
|
options
|
text
|
Extension status information. This is a reserved column in the system.
|