Why "drop procedure if exists konami" not working in mysql? - mysql

Question

I write a mysql script , it works fine :
use cloud_fight;
drop procedure if exists `konami`;
drop function if exists `rand_string`;
delimiter //
CREATE FUNCTION `rand_string`(n INT) RETURNS varchar(255)
BEGIN
DECLARE chars_str varchar(255) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789rew';
DECLARE return_str varchar(255) DEFAULT '';
DECLARE i INT DEFAULT 0;
while i < n do
SET return_str = concat(return_str,substring(chars_str , FLOOR(1 + RAND()*64 ),1));
SET i = i + 1;
END while;
RETURN return_str;
END //
delimiter $$
create procedure konami()
begin
declare q int default 1;
while q<=2 DO
set #N=rand_string(64);
insert into fight_user (user_guid , first_name , last_name , user_name , nick_name , gender , city , province , country , head_img_url , created_at , last_updated) values (#N, '' , '' , '' , rand_string(5) , '2' , 'bj' , 'bj' , 'cn' , '' , now() , now());
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'WECHAT_UNIONID' , now() , now() , 1 from fight_user where user_guid = #N;
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'MP_OPENID' , now() , now() , 1 from fight_user where user_guid = #N;
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'PA_OPENID' , now() , now() , 1 from fight_user where user_guid = #N;
set q=q+1;
end while;
end $$
call konami();
But when I move the command " drop procedure if exists konami " to the front of procedure konami() as shown below:
drop function if exists `rand_string`;
delimiter //
CREATE FUNCTION `rand_string`(n INT) RETURNS varchar(255)
BEGIN
DECLARE chars_str varchar(255) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789rew';
DECLARE return_str varchar(255) DEFAULT '';
DECLARE i INT DEFAULT 0;
while i < n do
SET return_str = concat(return_str,substring(chars_str , FLOOR(1 + RAND()*64 ),1));
SET i = i + 1;
END while;
RETURN return_str;
END //
drop procedure if exists `konami`;
delimiter $$
create procedure konami()
begin
declare q int default 1;
while q<=2 DO
set #N=rand_string(64);
insert into fight_user (user_guid , first_name , last_name , user_name , nick_name , gender , city , province , country , head_img_url , created_at , last_updated) values (#N, '' , '' , '' , rand_string(5) , '2' , 'bj' , 'bj' , 'cn' , '' , now() , now());
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'WECHAT_UNIONID' , now() , now() , 1 from fight_user where user_guid = #N;
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'MP_OPENID' , now() , now() , 1 from fight_user where user_guid = #N;
insert into fight_user_cake (fight_user_id , t_id , third_party_user_id , type , created_at , last_updated , status) select id , '2' , rand_string(20) , 'PA_OPENID' , now() , now() , 1 from fight_user where user_guid = #N;
set q=q+1;
end while;
end $$
call konami();
When I run the second script in mysql workbench 6.3.
It report error : Error Code: 1304. PROCEDURE konami already exists
So my question is when I move the command " drop procedure if exists konami " to the front of procedure konami() , why is this statement "drop procedure if exists konami" not working ?

Answer 1

Since you changed to DELIMITER // you need to use that delimiter at the end of each statement until you change it back.
DROP PROCEDURE and CREATE PROCEDURE are separate statements, and each requires its own statement delimiter.
DROP PROCEDURE IF EXISTS konami //