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.
procost float4   Estimated execution cost (in cpu_operator_cost units); if proretset is true, identifies the cost per row returned.
provariadic oid pg_type.oid Data type of the variadic array parameter's elements, or zero if the function does not have a variadic parameter.
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 int2   Number of arguments.
pronargdefaults int2   Number of arguments that have default values.
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 and VARIADIC 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, v = VARIADIC. 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.
proargdefaults text   Expression trees for default argument 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 is empty.
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.