| relname | name |  | Name of the table, index, view, etc. | 
| relnamespace | oid | pg_namespace.oid | The OID of the namespace that contains this relation | 
| reltype | oid | pg_type.oid | The OID of the data type that corresponds to this table's row type,
       if any (zero for indexes, which have no pg_type entry) | 
| relowner | oid | pg_authid.oid | Owner of the relation | 
| relam | oid | pg_am.oid | If this is an index, the access method used (B-tree, hash, etc.) | 
| relfilenode | oid |  | Name of the on-disk file of this relation; 0 if none | 
| reltablespace | oid | pg_tablespace.oid | The tablespace in which this relation is stored.  If zero,
       the database's default tablespace is implied.  (Not meaningful
       if the relation has no on-disk file.) | 
| relpages | int4 |  | Size of the on-disk representation of this table in pages (of size
       BLCKSZ).  This is only an estimate used by the
       planner.  It is updated by VACUUM,
       ANALYZE, and a few DDL commands such as
       CREATE INDEX | 
| reltuples | float4 |  | Number of rows in the table.  This is only an estimate used by the
       planner.  It is updated by VACUUM,
       ANALYZE, and a few DDL commands such as
       CREATE INDEX | 
| reltoastrelid | oid | pg_class.oid | OID of the TOAST table associated with this table, 0 if none.  The
       TOAST table stores large attributes "out of line" in a
       secondary table | 
| reltoastidxid | oid | pg_class.oid | For a TOAST table, the OID of its index.  0 if not a TOAST table | 
| relhasindex | bool |  | True if this is a table and it has (or recently had) any
       indexes. This is set by CREATE INDEX, but
       not cleared immediately by DROP INDEX.
       VACUUM clears relhasindex if it finds the
       table has no indexes | 
| relisshared | bool |  | True if this table is shared across all databases in the cluster.  Only
       certain system catalogs (such as pg_database)
       are shared | 
| relkind | char |  | r = ordinary table, i = index,
       S = sequence, v = view, c =
       composite type, t = TOAST
       table | 
| relnatts | int2 |  | Number of user columns in the relation (system columns not
       counted).  There must be this many corresponding entries in
       pg_attribute.  See also
       pg_attribute.attnum | 
| relchecks | int2 |  | Number of check constraints on the table; see
       pg_constraint catalog | 
| reltriggers | int2 |  | Number of triggers on the table; see
       pg_trigger catalog | 
| relukeys | int2 |  | Unused  (not the number of unique keys) | 
| relfkeys | int2 |  | Unused  (not the number of foreign keys on the table) | 
| relrefs | int2 |  | Unused | 
| relhasoids | bool |  | True if we generate an OID for each row of the relation | 
| relhaspkey | bool |  | True if the table has (or once had) a primary key | 
| relhasrules | bool |  | True if table has rules; see
       pg_rewrite catalog | 
| relhassubclass | bool |  | True if table has (or once had) any inheritance children | 
| relfrozenxid | xid |  | All transaction IDs before this one have been replaced with a permanent
       ("frozen") transaction ID in this table.  This is used to track
       whether the table needs to be vacuumed in order to prevent transaction
       ID wraparound or to allow pg_clog to be shrunk.  Zero
       (InvalidTransactionId) if the relation is not a table | 
| relacl | aclitem[] |  | Access privileges; see
       GRANT and
       REVOKE
       for details | 
| reloptions | text[] |  | Access-method-specific options, as "keyword=value" strings |