The catalog pg_largeobject_metadata holds metadata associated with large objects. The actual large object data is stored in pg_largeobject. Table 50-31. pg_largeobject_metadata Columns Name Type References Description oid oid Row identifier (hidden attribute; must be explicitly selected) lomowner oid pg_authid.oid Owner of the large object lomacl aclitem[] Access privileges; see GRANT and REVOKE for details Prev Next pg_largeobject Up pg_namespace

The catalog pg_largeobject holds the data making up "large objects". A large object is identified by an OID assigned when it is created. Each large object is broken into segments or "pages" small enough to be conveniently stored as rows in pg_largeobject. The amount of data per page is defined to be LOBLKSIZE (which is currently BLCKSZ/4, or typically 2 kB). Prior to PostgreSQL 9.0, there was no permission structure associated with large objects. As a result, pg_largeobject was publicly readabl

The catalog pg_language registers languages in which you can write functions or stored procedures. See CREATE LANGUAGE and Chapter 40 for more information about language handlers. Table 50-29. pg_language Columns Name Type References Description oid oid Row identifier (hidden attribute; must be explicitly selected) lanname name Name of the language lanowner oid pg_authid.oid Owner of the language lanispl bool This is false for internal languages (such as SQL) and true for user-defined l

The catalog pg_init_privs records information about the initial privileges of objects in the system. There is one entry for each object in the database which has a non-default (non-NULL) initial set of privileges. Objects can have initial privileges either by having those privileges set when the system is initialized (by initdb) or when the object is created during a CREATE EXTENSION and the extension script sets initial privileges using the GRANT system. Note that the system will automatically

The catalog pg_inherits records information about table inheritance hierarchies. There is one entry for each direct child table in the database. (Indirect inheritance can be determined by following chains of entries.) Table 50-27. pg_inherits Columns Name Type References Description inhrelid oid pg_class.oid The OID of the child table inhparent oid pg_class.oid The OID of the parent table inhseqno int4 If there is more than one direct parent for a child table (multiple inheritance), this nu

The view pg_indexes provides access to useful information about each index in the database. Table 50-65. pg_indexes Columns Name Type References Description schemaname name pg_namespace.nspname Name of schema containing table and index tablename name pg_class.relname Name of table the index is for indexname name pg_class.relname Name of index tablespace name pg_tablespace.spcname Name of tablespace containing index (null if default for database) indexdef text Index definition (a reconstruct

The catalog pg_index contains part of the information about indexes. The rest is mostly in pg_class. Table 50-26. pg_index Columns Name Type References Description indexrelid oid pg_class.oid The OID of the pg_class entry for this index indrelid oid pg_class.oid The OID of the pg_class entry for the table this index is for indnatts int2 The number of columns in the index (duplicates pg_class.relnatts) indisunique bool If true, this is a unique index indisprimary bool If true, this index

The view pg_group exists for backwards compatibility: it emulates a catalog that existed in PostgreSQL before version 8.1. It shows the names and members of all roles that are marked as not rolcanlogin, which is an approximation to the set of roles that are being used as groups. Table 50-64. pg_group Columns Name Type References Description groname name pg_authid.rolname Name of the group grosysid oid pg_authid.oid ID of this group grolist oid[] pg_authid.oid An array containing the IDs of th

The catalog pg_foreign_table contains auxiliary information about foreign tables. A foreign table is primarily represented by a pg_class entry, just like a regular table. Its pg_foreign_table entry contains the information that is pertinent only to foreign tables and not any other kind of relation. Table 50-25. pg_foreign_table Columns Name Type References Description ftrelid oid pg_class.oid OID of the pg_class entry for this foreign table ftserver oid pg_foreign_server.oid OID of the foreig

The catalog pg_foreign_server stores foreign server definitions. A foreign server describes a source of external data, such as a remote server. Foreign servers are accessed via foreign-data wrappers. Table 50-24. pg_foreign_server Columns Name Type References Description oid oid Row identifier (hidden attribute; must be explicitly selected) srvname name Name of the foreign server srvowner oid pg_authid.oid Owner of the foreign server srvfdw oid pg_foreign_data_wrapper.oid OID of the forei