mysql - 在mysql中创建存储过程

Question

这段代码有什么问题

CREATE DEFINER=`root`@`localhost` PROCEDURE `diff`()
BEGIN
    declare max_date datetime;
    declare tday_date datetime;
    declare main_id varchar(20);

    select concat('#GNC', '3') into main_id;  #error shows here


    declare m1 int;
    declare m2 int;
    select max(order_date) into max_date from `order`;
    #select max_date;
    select curdate() into tday_date;
    select extract(month from max_date) into m1;
    select extract(month from tday_date) into m2;

    if m1 != m2 then
        TRUNCATE `grocery`.`order_seqid`;
    end if;



    select m1, m2, main_id;
END

它给出了像缺少结尾这样的错误。如果我删除 if 语句，它就可以正常工作。

Answer 1

你就快到了:)我看到的唯一问题是你的所有声明都不是在你的逻辑的开头并且你没有使用@提到的分隔符阿尔瓦罗；试试这个:

DELIMITER $$

CREATE PROCEDURE `diff`()
  BEGIN
    declare max_date datetime;
    declare tday_date datetime;
    declare main_id varchar(20);
    declare m1 INT;
    declare m2 int;

    select concat('#GNC', '3') into main_id; 

     select max(order_date) into max_date from `order`;
    #select max_date;
    select curdate() into tday_date;
    select extract(month from max_date) into m1;
    select extract(month from tday_date) into m2;

    if m1 != m2 then
      TRUNCATE `grocery`.`order_seqid`;
    end if;



    select m1, m2, main_id;
  END $$