SYSTEM CATALOG · System catalog

pg_proc

PostgreSQL documentation ↗Source definition ↗

The catalog pg_proc stores information about functions, procedures, aggregate functions, and window functions (collectively also known as routines). See CREATE FUNCTION, CREATE PROCEDURE, and Section 36.3 for more information. If prokind indicates that the entry is for an aggregate function, there should be a matching row in pg_aggregate.

First seen PG 9.0Last seen PG 19Columns 30

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

Checked column by column against a PostgreSQL 18.6 instance · Raw measurement record ↗

Columns PostgreSQL 18

pg_proc

COLUMN	TYPE	DESCRIPTION
`oid`	`oid`NOT NULL	Row identifier
`proname`	`name`NOT NULL	Name of the function
`pronamespace`	`oid`NOT NULL	The OID of the namespace that contains this functionReferences:`pg_namespace.oid`
`proowner`	`oid`NOT NULL	Owner of the functionReferences:`pg_authid.oid`
`prolang`	`oid`NOT NULL	Implementation language or call interface of this functionReferences:`pg_language.oid`
`procost`	`real`NOT NULLDocumented as:`float4`	Estimated execution cost (in units of cpu_operator_cost); if proretset, this is cost per row returned
`prorows`	`real`NOT NULLDocumented as:`float4`	Estimated number of result rows (zero if not proretset)
`provariadic`	`oid`NOT NULL	Data type of the variadic array parameter's elements, or zero if the function does not have a variadic parameterReferences:`pg_type.oid`
`prosupport`	`regproc`NOT NULL	Planner support function for this function (see Section 36.11), or zero if noneReferences:`pg_proc.oid`
`prokind`	`"char"`NOT NULLDocumented as:`char`	f for a normal function, p for a procedure, a for an aggregate function, or w for a window function
`prosecdef`	`boolean`NOT NULLDocumented as:`bool`	Function is a security definer (i.e., a “setuid” function)
`proleakproof`	`boolean`NOT NULLDocumented as:`bool`	The function has no side effects. No information about the arguments is conveyed except via the return value. Any function that might throw an error depending on the values of its arguments is not leakproof.
`proisstrict`	`boolean`NOT NULLDocumented as:`bool`	Function returns null if any call argument is null. In that case the function won't actually be called at all. Functions that are not “strict” must be prepared to handle null inputs.
`proretset`	`boolean`NOT NULLDocumented as:`bool`	Function returns a set (i.e., multiple values of the specified data type)
`provolatile`	`"char"`NOT NULLDocumented as:`char`	provolatile tells whether the function's result depends only on its input arguments, or is affected by outside factors. It is i for “immutable” functions, which always deliver the same result for the same inputs. It is s for “stable” functions, whose results (for fixed inputs) do not change within a scan. It is v for “volatile” functions, whose results might change at any time. (Use v also for functions with side-effects, so that calls to them cannot get optimized away.)
`proparallel`	`"char"`NOT NULLDocumented as:`char`	proparallel tells whether the function can be safely run in parallel mode. It is s for functions which are safe to run in parallel mode without restriction. It is r for functions which can be run in parallel mode, but their execution is restricted to the parallel group leader; parallel worker processes cannot invoke these functions. It is u for functions which are unsafe in parallel mode; the presence of such a function forces a serial execution plan.
`pronargs`	`smallint`NOT NULLDocumented as:`int2`	Number of input arguments
`pronargdefaults`	`smallint`NOT NULLDocumented as:`int2`	Number of arguments that have defaults
`prorettype`	`oid`NOT NULL	Data type of the return valueReferences:`pg_type.oid`
`proargtypes`	`oidvector`NOT NULL	An array of the data types of the function arguments. This includes only input arguments (including INOUT and VARIADIC arguments), and thus represents the call signature of the function.References:`pg_type.oid`
`proallargtypes`	`oid[]`	An array of the data types of the function arguments. This includes all arguments (including OUT and INOUT arguments); however, if all the arguments are IN arguments, this field will be null. Note that subscripting is 1-based, whereas for historical reasons proargtypes is subscripted from 0.References:`pg_type.oid`
`proargmodes`	`"char"[]`Documented as:`char[]`	An array of the modes of the function arguments, encoded as i for IN arguments, o for OUT arguments, b for INOUT arguments, v for VARIADIC arguments, t for TABLE arguments. If all the arguments are IN arguments, this field will be null. Note that subscripts correspond to positions of proallargtypes not proargtypes.
`proargnames`	`text[]`	An array of the names of the function arguments. Arguments without a name are set to empty strings in the array. If none of the arguments have a name, this field will be null. Note that subscripts correspond to positions of proallargtypes not proargtypes.
`proargdefaults`	`pg_node_tree`	Expression trees (in nodeToString() representation) for default values. This is a list with pronargdefaults elements, corresponding to the last N input arguments (i.e., the last N proargtypes positions). If none of the arguments have defaults, this field will be null.
`protrftypes`	`oid[]`	An array of the argument/result data type(s) for which to apply transforms (from the function's TRANSFORM clause). Null if none.References:`pg_type.oid`
`prosrc`	`text`NOT NULL	This tells the function handler how to invoke the function. It might be the actual source code of the function for interpreted languages, a link symbol, a file name, or just about anything else, depending on the implementation language/call convention.
`probin`	`text`	Additional information about how to invoke the function. Again, the interpretation is language-specific.
`prosqlbody`	`pg_node_tree`	Pre-parsed SQL function body. This is used for SQL-language functions when the body is given in SQL-standard notation rather than as a string literal. It's null in other cases.
`proconfig`	`text[]`	Function's local settings for run-time configuration variables
`proacl`	`aclitem[]`	Access privileges; see Section 5.8 for details

Columns marked "implicit" are not included in SELECT *; some early statistics views are completed from same-version source, and the extra provenance is shown in the column description.

Common system columns 6

System attributes PostgreSQL provides, normally not expanded by SELECT *. Kept separately so they are not mixed in with ordinary columns.

Columns	Type	attnum
`tableoid`	`oid`	-6
`cmax`	`cid`	-5
`xmax`	`xid`	-4
`cmin`	`cid`	-3
`xmin`	`xid`	-2
`ctid`	`tid`	-1

Column evolution matrix

Hover a cell for the column type

PresentAdded / type or attribute changeRemoved

COLUMN	9.0	9.1	9.2	9.3	9.4	9.5	9.6	10	11	12	13	14	15	16	17	18	19
`oid`
`proname`
`pronamespace`
`proowner`
`prolang`
`procost`
`prorows`
`provariadic`
`proisagg`									−	–	–	–	–	–	–	–	–
`proiswindow`									−	–	–	–	–	–	–	–	–
`prosecdef`
`proisstrict`
`proretset`
`provolatile`
`pronargs`
`pronargdefaults`
`prorettype`
`proargtypes`
`proallargtypes`
`proargmodes`
`proargnames`
`proargdefaults`
`prosrc`
`probin`
`proconfig`
`proacl`
`protransform`	–	–								−	–	–	–	–	–	–	–
`proleakproof`	–	–
`protrftypes`	–	–	–	–	–
`proparallel`	–	–	–	–	–	–
`prokind`	–	–	–	–	–	–	–	–
`prosupport`	–	–	–	–	–	–	–	–	–
`prosqlbody`	–	–	–	–	–	–	–	–	–	–	–

9.0 is the coverage baseline; a column already present in the baseline is not marked as added. The matrix aligns columns by name, so a rename appears as the old column removed and a new column added.

Evolution timeline

Changes between adjacent majors

PostgreSQL 19 ← 18

1 column description updates

PostgreSQL 18 ← 17

1 column description updates

PostgreSQL 17 ← 16

2 column description updatesCatalog description updated

PostgreSQL 14 ← 13

+ prosqlbody1 column description updatesCatalog description updated

PostgreSQL 13 ← 12

5 column description updates1 reference updates

PostgreSQL 12 ← 11

+ prosupport− protransform~ oid: implicit → ordinary2 column description updatesCatalog description updated

PostgreSQL 11 ← 10

+ prokind− proisagg− proiswindow1 column description updatesCatalog description updated

PostgreSQL 10 ← 9.6

4 column description updatesCatalog description updated

PostgreSQL 9.6 ← 9.5

+ proparallel1 column description updatesCatalog description updated

PostgreSQL 9.5 ← 9.4

+ protrftypes~ prosrc: not_null: false → true

PostgreSQL 9.3 ← 9.2

1 column description updates

PostgreSQL 9.2 ← 9.1

+ protransform+ proleakproof

PostgreSQL 9.1 ← 9.0

~ proargdefaults: text → pg_node_tree

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