pg_proc

pg_proc

The pg_proc system catalog table stores information about functions (or procedures), both built-in functions and those defined by CREATE FUNCTION. The table contains data for aggregate and window functions as well as plain functions. If proisagg is true, there should be a matching row in pg_aggregate. If proiswin is true, there should be a matching row in pg_window.

For compiled functions, both built-in and dynamically loaded, prosrc contains the function’s C-language name (link symbol). For all other currently-known language types, prosrc contains the function’s source text. probin is unused except for dynamically-loaded C functions, for which it gives the name of the shared library file containing the function.

Table 1. pg_catalog.pg_proc

column	type	references	description
`proname`	name		Name of the function.
`pronamespace`	oid	pg_namespace.oid	The OID of the namespace that contains this function.
`proowner`	oid	pg_authid.oid	Owner of the function.
`prolang`	oid	pg_language.oid	Implementation language or call interface of this function.
`proisagg`	boolean		Function is an aggregate function.
`prosecdef`	boolean		Function is a security definer (for example, a ‘setuid’ function).
`proisstrict`	boolean		Function returns NULL if any call argument is NULL. In that case the function will not actually be called at all. Functions that are not strict must be prepared to handle NULL inputs.
`proretset`	boolean		Function returns a set (multiple values of the specified data type).
`provolatile`	char		Tells whether the function’s result depends only on its input arguments, or is affected by outside factors. `i` = immutable (always delivers the same result for the same inputs), `s` = stable (results (for fixed inputs) do not change within a scan), or `v` = volatile (results may change at any time or functions with side-effects).
`pronargs`	smallint		Number of arguments.
`prorettype`	oid	pg_type.oid	Data type of the return value.
`proiswin`	boolean		Function is neither an aggregate nor a scalar function, but a pure window function.
`proargtypes`	oidvector	pg_type.oid	An array with the data types of the function arguments. This includes only input arguments (including `INOUT` arguments), and thus represents the call signature of the function.
`proallargtypes`	oid[]	pg_type.oid	An array with 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.
`proargmodes`	char[]		An array with the modes of the function arguments: `i` = `IN`, `o` = `OUT` , `b` = `INOUT`. 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 with 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.
`prosrc`	text		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`	bytea		Additional information about how to invoke the function. Again, the interpretation is language-specific.
`proacl`	aclitem[]		Access privileges for the function as given by `GRANT`/`REVOKE`.