The pg_partition system catalog table is used to track partitioned tables and their inheritance level relationships. Each row of pg_partition represents either the level of a partitioned table in the partition hierarchy, or a subpartition template description. The value of the attribute paristemplate determines what a particular row represents.

Table 1. pg_catalog.pg_partition

column type references description
parrelid oid pg_class.oid The object identifier of the table.
parkind char   The partition type - R for range or L for list.
parlevel smallint   The partition level of this row: 0 for the top-level parent table, 1 for the first level under the parent table, 2 for the second level, and so on.
paristemplate boolean   Whether or not this row represents a subpartition template definition (true) or an actual partitioning level (false).
parnatts smallint   The number of attributes that define this level.
paratts int2vector   An array of the attribute numbers (as in pg_attribute.attnum) of the attributes that participate in defining this level.
parclass oidvector pg_opclass.oid The operator class identifier(s) of the partition columns.