The pg_partitioned_table
system catalog stores information about how tables are partitioned.
column | type | references | description |
---|---|---|---|
partrelid |
oid | pg_class.oid | The object identifier of the pg_class entry for this partitioned table. |
partstrat |
char | The partitioning strategy: h = hash partitioned table, l = list partitioned table, r = range partitioned table. |
|
partnatts |
smallint | The number of columns in the partition key. | |
partdefid |
oid | pg_class.oid | The object identifier of the pg_class entry for the default partition of this partitioned table, or zero if this partitioned table does not have a default partition. |
partattrs |
int2vector | pg_attribute.attnum | An array of partnatts values that indicate which table columns are part of the partition key. For example, a value of 1 3 would mean that the first and the third table columns make up the partition key. A zero in this array indicates that the corresponding partition key column is an expression, rather than a simple column reference. |
partclass |
oidvector | pg_opclass.oid | For each column in the partition key, contains the object identifier of the operator class to use. See pg_opclass for details. |
partcollation |
oidvector | pg_opclass.oid | For each column in the partition key, contains the object identifier of the collation to use for partitioning, or zero if the column is not of a collatable data type. |
partexprs |
pg_node_tree | Expression trees (in nodeToString() representation) for partition key columns that are not simple column references. This list contains one element for each zero entry in partattrs . Null if all partition key columns are simple references. Greenplum Database classic partition syntax does not support specifying an expression in a partition key. |
Parent topic: System Catalogs Definitions