name
The name (optionally schema-qualified) of the procedure to create.
argmode
The mode of an argument: IN, OUT, INOUT, or VARIADIC. If omitted, the default is IN.
argname
The name of an argument.
argtype
The data type(s) of the procedure's arguments (optionally schema-qualified), if any. The argument
types can be base, composite, or domain types, or can reference the type of a table column.
Depending on the implementation language it might also be allowed to specify “pseudo-types” such as
cstring. Pseudo-types indicate that the actual argument type is either incompletely specified, or
outside the set of ordinary SQL data types.
The type of a column is referenced by writing table_name.column_name%TYPE. Using this feature can
sometimes help make a procedure independent of changes to the definition of a table.
default_expr
An expression to be used as default value if the parameter is not specified. The expression has to be
coercible to the argument type of the parameter. All input parameters following a parameter with a
default value must have default values as well.
lang_name
The name of the language that the procedure is implemented in. It can be sql, c, internal, or the
name of a user-defined procedural language, e.g., plpgsql. The default is sql if sql_body is
specified. Enclosing the name in single quotes is deprecated and requires matching case.
TRANSFORM { FOR TYPE type_name } [, ... ] }
Lists which transforms a call to the procedure should apply. Transforms convert between SQL types and
language-specific data types; see CREATE TRANSFORM (CREATE_TRANSFORM(7)). Procedural language
implementations usually have hardcoded knowledge of the built-in types, so those don't need to be
listed here. If a procedural language implementation does not know how to handle a type and no
transform is supplied, it will fall back to a default behavior for converting data types, but this
depends on the implementation.
[EXTERNAL] SECURITY INVOKER
[EXTERNAL] SECURITY DEFINER
SECURITY INVOKER indicates that the procedure is to be executed with the privileges of the user that
calls it. That is the default. SECURITY DEFINER specifies that the procedure is to be executed with
the privileges of the user that owns it.
The key word EXTERNAL is allowed for SQL conformance, but it is optional since, unlike in SQL, this
feature applies to all procedures not only external ones.
A SECURITY DEFINER procedure cannot execute transaction control statements (for example, COMMIT and
ROLLBACK, depending on the language).
configuration_parametervalue
The SET clause causes the specified configuration parameter to be set to the specified value when the
procedure is entered, and then restored to its prior value when the procedure exits. SET FROM
CURRENT saves the value of the parameter that is current when CREATEPROCEDURE is executed as the
value to be applied when the procedure is entered.
If a SET clause is attached to a procedure, then the effects of a SETLOCAL command executed inside
the procedure for the same variable are restricted to the procedure: the configuration parameter's
prior value is still restored at procedure exit. However, an ordinary SET command (without LOCAL)
overrides the SET clause, much as it would do for a previous SETLOCAL command: the effects of such a
command will persist after procedure exit, unless the current transaction is rolled back.
If a SET clause is attached to a procedure, then that procedure cannot execute transaction control
statements (for example, COMMIT and ROLLBACK, depending on the language).
See SET(7) and Chapter 19 for more information about allowed parameter names and values.
definition
A string constant defining the procedure; the meaning depends on the language. It can be an internal
procedure name, the path to an object file, an SQL command, or text in a procedural language.
It is often helpful to use dollar quoting (see Section 4.1.2.4) to write the procedure definition
string, rather than the normal single quote syntax. Without dollar quoting, any single quotes or
backslashes in the procedure definition must be escaped by doubling them.
obj_file, link_symbol
This form of the AS clause is used for dynamically loadable C language procedures when the procedure
name in the C language source code is not the same as the name of the SQL procedure. The string
obj_file is the name of the shared library file containing the compiled C procedure, and is
interpreted as for the LOAD command. The string link_symbol is the procedure's link symbol, that is,
the name of the procedure in the C language source code. If the link symbol is omitted, it is assumed
to be the same as the name of the SQL procedure being defined.
When repeated CREATEPROCEDURE calls refer to the same object file, the file is only loaded once per
session. To unload and reload the file (perhaps during development), start a new session.
sql_body
The body of a LANGUAGE SQL procedure. This should be a block
BEGIN ATOMIC
statement;
statement;
...
statement;
END
This is similar to writing the text of the procedure body as a string constant (see definition
above), but there are some differences: This form only works for LANGUAGE SQL, the string constant
form works for all languages. This form is parsed at procedure definition time, the string constant
form is parsed at execution time; therefore this form cannot support polymorphic argument types and
other constructs that are not resolvable at procedure definition time. This form tracks dependencies
between the procedure and objects used in the procedure body, so DROP ... CASCADE will work
correctly, whereas the form using string literals may leave dangling procedures. Finally, this form
is more compatible with the SQL standard and other SQL implementations.