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。
pg_proc
Columns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。
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[]