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HomeDatabaseMysql Tutorialmysql创建存储过程和函数_MySQL

bitsCN.com mysql创建存储过程和函数 一个存储程序是可以被存储在服务器中的一套SQL语句。可以通过客户端用CREATE PROCEDURE和CREATE FUNCTION  创建一个存储过程或函数。在客户端通过CALL语句 调用所创建的存数过程或函数。 语法: 创建存储子程序: 01CREATE PROCEDURE sp_name ([proc_parameter[,...]])02    [characteristic ...] routine_body03CREATE FUNCTION sp_name ([func_parameter[,...]])04    RETURNS type05    [characteristic ...] routine_body06    proc_parameter:07    [ IN | OUT | INOUT ] param_name type08    func_parameter:09    param_name type10    type:11    Any valid MySQL data type12characteristic:13    LANGUAGE SQL14  | [NOT] DETERMINISTIC15  | { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA }16  | SQL SECURITY { DEFINER | INVOKER }17  | COMMENT 'string'18routine_body:19    Valid SQL procedure statement or statements
 默认地,子程序与当前数据库关联。要明确地把子程序与一个给定数据库关联起来,可以在创建子程序的时候指定其名字为db_name.sp_name。在 程序被定义的时候,用mysql客户端delimiter命令来把语句定界符从 ;变为//。这就允许用在 程序体中的;定界符被传递到服务器而不是被mysql自己来解释。例如: 01mysql> delimiter //02mysql> CREATE PROCEDURE simpleproc (OUT param1 INT)03    -> BEGIN04    ->   SELECT COUNT(*) INTO param1 FROM t;05    -> END    06    -> //07Query OK, 0 rows affected (0.00 sec)08mysql> delimiter ;09mysql> CALL simpleproc(@a);10Query OK, 0 rows affected (0.00 sec)11mysql> SELECT @a;12+------+13| @a   |14+------+15| 3    |16+------+171 row in set (0.00 sec)01mysql> delimiter //02mysql> CREATE FUNCTION hello (s CHAR(20)) RETURNS CHAR(50)03    -> RETURN CONCAT('Hello, ',s,'!');04    -> //05Query OK, 0 rows affected (0.00 sec)06mysql> delimiter ;07    mysql> SELECT hello('world');08+----------------+09| hello('world') |10+----------------+11| Hello, world!  |12+----------------+131 row in set (0.00 sec)   作者 蜜蜜 bitsCN.com

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