# pg_partition_rule

The `pg_partition_rule` system catalog table is used to track partitioned tables, their check constraints, and data containment rules. Each row of `pg_partition_rule` represents either a leaf partition (the bottom level partitions that contain data), or a branch partition (a top or mid-level partition that is used to define the partition hierarchy, but does not contain any data).



Table 1. `pg_catalog.pg_partition_rule`

| column              | type     | references               | description                                                  |
| :------------------ | :------- | :----------------------- | :----------------------------------------------------------- |
| `parrootrelid`      | oid      |                          | The OID of root table.                                       |
| `paroid`            | oid      | pg_partition.oid         | Row identifier of the partitioning level (from [pg_partition](./pg_partition.md)) to which this partition belongs. In the case of a branch partition, the corresponding table (identified by `pg_partition_rule`) is an empty container table. In case of a leaf partition, the table contains the rows for that partition containment rule. |
| `parchildrelid`     | oid      | pg_class_internal.oid    | The table identifier of the partition (child table).         |
| `parparentrule`     | oid      | pg_partition_rule.paroid | The row identifier of the rule associated with the parent table of this partition. |
| `parname`           | name     |                          | The given name of this partition.                            |
| `parisdefault`      | boolean  |                          | Whether or not this partition is a default partition.        |
| `parruleord`        | smallint |                          | For range partitioned tables, the rank of this partition on this level of the partition hierarchy. |
| `parrangestartincl` | boolean  |                          | For range partitioned tables, whether or not the starting value is inclusive. |
| `parrangeendincl`   | boolean  |                          | For range partitioned tables, whether or not the ending value is inclusive. |
| `parrangestart`     | text     |                          | For range partitioned tables, the starting value of the range. |
| `parrangeend`       | text     |                          | For range partitioned tables, the ending value of the range. |
| `parrangeevery`     | text     |                          | For range partitioned tables, the interval value of the `EVERY` clause. |
| `parlistvalues`     | text     |                          | For list partitioned tables, the list of values assigned to this partition. |
| `parreloptions`     | text     |                          | An array describing the storage characteristics of the particular partition. |
| `partemplatespace`  | oid      |                          |                                                              |