mysql 存储过程 例子

DROP PROCEDURE IF EXISTS variable_demo;
delimiter //   
CREATE PROCEDURE variable_demo()
BEGIN
select 'hello world!';
 
END;//
delimiter ;




DROP PROCEDURE IF EXISTS demo1;
delimiter //   
CREATE PROCEDURE demo1(IN type int)
BEGIN
    DECLARE c varchar(500);
    IF type = 0 THEN
        set c = 'param is 0';
    ELSEIF type = 1 THEN
        set c = 'param is 1';
    ELSE
        set c = 'param is others, not 0 or 1';
    END IF;
    select c;
END;//
delimiter ;



DROP PROCEDURE IF EXISTS demo2;
delimiter //   
CREATE PROCEDURE demo2(IN type int)
BEGIN
    DECLARE c varchar(500);
    CASE type
    WHEN 0 THEN
        set c = 'param is 0';
    WHEN 1 THEN
        set c = 'param is 1';
    ELSE
        set c = 'param is others, not 0 or 1';
    END CASE;
    select c;
END;//
delimiter ;



DROP PROCEDURE IF EXISTS demo3;
delimiter //   
CREATE PROCEDURE demo3()
BEGIN
    declare type int;
    DECLARE c varchar(500);
    declare i int;
    set i=0;
    while i<10 do
    
    IF i = 0 THEN
        set c = 'param is 0';
    ELSEIF i = 1 THEN
        set c = 'param is 1';
    ELSE
        set c = 'param is others, not 0 or 1';
    END IF;
    select c;
    set i=i+1;

    end while;
END;//
delimiter ;


//sql语句的操作


DROP PROCEDURE IF EXISTS demo4;
delimiter //
create PROCEDURE  demo4()
begin
declare cnt int;
select count(*) into cnt from user_order_detail_1;
select cnt;



end; //
delimiter ;



DROP PROCEDURE IF EXISTS demo5;
delimiter //
create PROCEDURE  demo5()
begin
declare cnt int;
while select count(*) into cnt from user_order_detail_1 do

end loop;
select cnt;



end; //
delimiter ;