POSTGRESQL FUNCTION 介绍

CREATE OR REPLACE FUNCTION ADDN (_a int,_b int)  
RETURNS integer AS $total$  
declare  
    total integer;  
BEGIN  
   total :=_a+_b;
   raise notice '%+%=%',_a,_b,total;
   RETURN total;  
END;  
$total$ LANGUAGE plpgsql;

CREATE OR REPLACE FUNCTION ADDN(_a INT,_b INT) RETURNS INTEGER AS $$
BEGIN
	RETURN _a+_b;
END;
$$ LANGUAGE PLPGSQL;

CREATE OR REPLACE FUNCTION ADDN(INT,INT) RETURNS INTEGER 
AS 'SELECT $1+$2;'
LANGUAGE SQL
IMMUTABLE
RETURNS NULL ON NULL INPUT;

CREATE OR REPLACE FUNCTION ADDN(_a INT,_b INT) RETURNS INTEGER 
AS 'SELECT _a+_b;'
LANGUAGE SQL;

CREATE OR REPLACE FUNCTION ADDN(INT,INT) RETURNS INTEGER
AS 'SELECT $1+$2'
LANGUAGE SQL;

函数返回多结果集

PostgreSQL存储过程(1)-基于SQL的存储过程

PostgreSQL存储过程(2)-基于PL/PgSQL的存储过程

PostgreSQL存储过程(3)-流程控制语句

PostgreSQL存储过程(4)-return语句

PostgreSQL存储过程(5)-异常错误处理