Wiki / OID Types

Object identifiers, reg* name aliases, and the transaction, command and row identifiers documented alongside them.

Reading PostgreSQL 18.6.

Find an entry GroupAll groupsObject identifiers (2)Object name aliases (12)Transaction and row identifiers (4) Apply

18 entries; 16 recorded in PostgreSQL 18.6.

• oid Object identifiers

  oid

  numeric object identifier.

  1011121314151617181920
• oid8 Object identifiers not in 18

  oid8

  Not recorded in the selected version.

  1011121314151617181920
• regclass Object name aliases

  regclass

  relation name.

  1011121314151617181920
• regcollation Object name aliases

  regcollation

  collation name.

  1011121314151617181920
• regconfig Object name aliases

  regconfig

  text search configuration.

  1011121314151617181920
• regdatabase Object name aliases not in 18

  regdatabase

  Not recorded in the selected version.

  1011121314151617181920
• regdictionary Object name aliases

  regdictionary

  text search dictionary.

  1011121314151617181920
• regnamespace Object name aliases

  regnamespace

  namespace name.

  1011121314151617181920
• regoper Object name aliases

  regoper

  operator name.

  1011121314151617181920
• regoperator Object name aliases

  regoperator

  operator with argument types.

  1011121314151617181920
• regproc Object name aliases

  regproc

  function name.

  1011121314151617181920
• regprocedure Object name aliases

  regprocedure

  function with argument types.

  1011121314151617181920
• regrole Object name aliases

  regrole

  role name.

  1011121314151617181920
• regtype Object name aliases

  regtype

  data type name.

  1011121314151617181920
• cid Transaction and row identifiers

  cid

  A third identifier type used by the system is cid , or command identifier. This is the data type of the system columns cmin and cmax . Command identifiers are also 32-bit quantities.

  1011121314151617181920
• tid Transaction and row identifiers

  tid

  A final identifier type used by the system is tid , or tuple identifier (row identifier). This is the data type of the system column ctid . A tuple ID is a pair (block number, tuple index within block) that identifies the physical location of the ro…

  1011121314151617181920
• xid Transaction and row identifiers

  xid

  Another identifier type used by the system is xid , or transaction (abbreviated xact ) identifier. This is the data type of the system columns xmin and xmax . Transaction identifiers are 32-bit quantities. In some contexts, a 64-bit variant xid8 is …

  1011121314151617181920
• xid8 Transaction and row identifiers

  xid8

  Another identifier type used by the system is xid , or transaction (abbreviated xact ) identifier. This is the data type of the system columns xmin and xmax . Transaction identifiers are 32-bit quantities. In some contexts, a 64-bit variant xid8 is …

  1011121314151617181920

RecordedFirst recordedInterface or attribute changeNo longer recorded

Squares indicate presence in sampled builds, not first introduction. Select a square for the same-version definition and sources.

Changes in PostgreSQL 18.6 · Export JSON

Reading this collection

Name aliases resolve catalog objects. Bare OIDs are not persistent identities across databases or clusters; transaction identifiers and physical row locations have different lifetimes.