pg_aggregate

The catalog pg_aggregate stores information about aggregate functions.

Reading PG 18current·documented in 24 of 24 versions, 7.4 to 20

7.4 8.0 8.1 8.2 8.3 8.4 9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19 20

Kind: System catalogs
Columns in this snapshot: 22
Definition source: English manual
Metadata snapshot: 18.6

Columns 22

As listed in the PostgreSQL 18 manual.

Column	Type	Description / reference
`aggfnoid`	`regproc`NOT NULL	pg_proc OID of the aggregate function pg_proc.oid
`aggkind`	`char`NOT NULL	Aggregate kind: n for “normal” aggregates, o for “ordered-set” aggregates, or h for “hypothetical-set” aggregates
`aggnumdirectargs`	`int2`NOT NULL	Number of direct (non-aggregated) arguments of an ordered-set or hypothetical-set aggregate, counting a variadic array as one argument. If equal to pronargs, the aggregate must be variadic and the variadic array describes the aggregated arguments as well as the final direct arguments. Always zero for normal aggregates.
`aggtransfn`	`regproc`NOT NULL	Transition function pg_proc.oid
`aggfinalfn`	`regproc`NOT NULL	Final function (zero if none) pg_proc.oid
`aggcombinefn`	`regproc`NOT NULL	Combine function (zero if none) pg_proc.oid
`aggserialfn`	`regproc`NOT NULL	Serialization function (zero if none) pg_proc.oid
`aggdeserialfn`	`regproc`NOT NULL	Deserialization function (zero if none) pg_proc.oid
`aggmtransfn`	`regproc`NOT NULL	Forward transition function for moving-aggregate mode (zero if none) pg_proc.oid
`aggminvtransfn`	`regproc`NOT NULL	Inverse transition function for moving-aggregate mode (zero if none) pg_proc.oid
`aggmfinalfn`	`regproc`NOT NULL	Final function for moving-aggregate mode (zero if none) pg_proc.oid
`aggfinalextra`	`bool`NOT NULL	True to pass extra dummy arguments to aggfinalfn
`aggmfinalextra`	`bool`NOT NULL	True to pass extra dummy arguments to aggmfinalfn
`aggfinalmodify`	`char`NOT NULL	Whether aggfinalfn modifies the transition state value: r if it is read-only, s if the aggtransfn cannot be applied after the aggfinalfn, or w if it writes on the value
`aggmfinalmodify`	`char`NOT NULL	Like aggfinalmodify, but for the aggmfinalfn
`aggsortop`	`oid`NOT NULL	Associated sort operator (zero if none) pg_operator.oid
`aggtranstype`	`oid`NOT NULL	Data type of the aggregate function's internal transition (state) data pg_type.oid
`aggtransspace`	`int4`NOT NULL	Approximate average size (in bytes) of the transition state data, or zero to use a default estimate
`aggmtranstype`	`oid`NOT NULL	Data type of the aggregate function's internal transition (state) data for moving-aggregate mode (zero if none) pg_type.oid
`aggmtransspace`	`int4`NOT NULL	Approximate average size (in bytes) of the transition state data for moving-aggregate mode, or zero to use a default estimate
`agginitval`	`text`	The initial value of the transition state. This is a text field containing the initial value in its external string representation. If this field is null, the transition state value starts out null.
`aggminitval`	`text`	The initial value of the transition state for moving-aggregate mode. This is a text field containing the initial value in its external string representation. If this field is null, the transition state value starts out null.