51.39. pg_proc

目錄 pg_proc 儲存有關函數、程序函數、彙總函數和窗函數（或統稱為 routines）的資訊。 有關更多資訊，請參閱 CREATE FUNCTION，CREATE PROCEDURE 和第 37.3 節。

如果 prokind 指示該項目用於彙總函數，則 pg_aggregate 中應有相對應的資料列。

Table 51.39. pg_proc Columns

Name	Type	References	Description
oid	oid		Row identifier (hidden attribute; must be explicitly selected)
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 units of cpu_operator_cost); if proretset, this is cost per row returned
prorows	float4		Estimated number of result rows (zero if not proretset)
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
protransform	regproc	pg_proc.oid	Calls to this function can be simplified by this other function (see Section 38.10.10)
prokind	char		f for a normal function, p for a procedure, a for an aggregate function, or w for a window function
prosecdef	bool		Function is a security definer (i.e., a “setuid” function)
proleakproof	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 leak-proof.
proisstrict	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	bool		Function returns a set (i.e., multiple values of the specified data type)
provolatile	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		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	int2		Number of input arguments
pronargdefaults	int2		Number of arguments that have defaults
prorettype	oid	pg_type.oid	Data type of the return value
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, 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 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	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[]		Data type OIDs for which to apply transforms.
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	text		Additional information about how to invoke the function. Again, the interpretation is language-specific.
proconfig	text[]		Function's local settings for run-time configuration variables
proacl	aclitem[]		Access privileges; see GRANT and REVOKE for details

對於內建和動態載入的已編譯函數，prosrc 包含函數的 C 語言名稱（link symbol）。 對於所有其他目前已知的語言類型，prosrc 包含函數的原始碼。除了動態載入的 C 函數外，probin 均未使用，因為它用於記錄該函數的共享函式庫檔案的名稱。