The name of an argument. Some languages (including SQL and PL/pgSQL) let you use the name in the function body. For other languages the name of an input argument is just extra documentation, so far as the funct
在PostgreSQL中,使用PL/pgSQL语言创建函数的基本语法如下: sql CREATE OR REPLACE FUNCTION function_name (parameters) RETURNS return_datatype AS $$ BEGIN -- 函数体 END; $$ LANGUAGE plpgsql; CREATE OR REPLACE FUNCTION:用于创建或替换一个函数。 function_name:函数的名称。 parameters:函数的参数列表,格...
在PL/pgSQL中,使用一个参数名称增加一个整数: CREATE OR REPLACE FUNCTION increment(i integer) RETURNS integer AS $$ BEGIN RETURN i + 1; END; $$ LANGUAGE plpgsql; 返回一个包含多个输出参数的记录: CREATE FUNCTION dup(in int, out f1 int, out f2 text) AS $$ SELECT $1, CAST($1 AS text...
示例:创建一个处理整数自增的PL/pgSQL语言的函数 语法如下: CREATE OR REPLACE FUNCTION func_increment_plsql( i integer --输入参数,整数类型 ) RETURNS integer --函数返回值为整数类型 AS $$ BEGIN --表示函数体开始 RETURN i + 1; --返回输入参数加1的结果 END; $$ LANGUAGE plpgsql; --指定函数使...
For PL/pgSQL functions, afterbehavior_compat_optionsis set to'proc_outparam_override', the restrictions are as follows: If a function with theout/inoutparameter already exists in the same schema or package, you cannot create another function with the same name with theout/inoutparameter. ...
Creates a function.If the parameters or return values of a function have precision, the precision is not checked.When creating a function, you are advised to explicitly s
在PL/pgSQL中,使用一个参数名称增加一个整数: CREATE OR REPLACE FUNCTION increment(i integer) RETURNS integer AS $$ BEGIN RETURN i + 1; END; $$ LANGUAGE plpgsql; 返回一个包含多个输出参数的记录: CREATE FUNCTION dup(in int, out f1 int, out f2 text) AS $$ SELECT $1, CAST($1 AS text...
CREATE [ OR REPLACE ] FUNCTION name ( [ [ argmode ] [ argname ] argtype [ { DEFAULT | = } default_expr ] [, ...] ] ) [ RETURNS rettype | RETURNS TABLE ( column_name column_type [, ...] ) ] { LANGUAGE lang_name | TRANSFORM { FOR TYPE type_name } [, ... ] | WINDO...
Procedural language functions, written in a supported procedural language such as PL.pgSQL. Internal functions. C-language functions. In addition, the purpose of the function can also be categorized asvolatile,immutable, orstable. Avolatile(the default) function can modify t...
In the above syntax, the language used to create the trigger function is PL/pgSQL but we can create it using any of the languages supported by PostgreSQL. The trigger function gets the information about its calling event through TriggerData, which contains some set of local variables. For exa...