Question

嘿伙计们，有人会在我的mysql代码中指出我的错误我试图创建一个在触发器中调用的存储过程是一个用户在books表中插入一本新书，如果callNumber不存在则bookqty表插入并在存在时更新，但在某些时候插入查询不起作用但更新查询工作正常提前谢谢你

use librarydb;
drop procedure if exists intoBooksQty;
delimiter $$

    create procedure intoBooksQty(in newcallNumber varchar(10))

        begin
            if not exists (select * from books where callNumber = newcallNumber) then
                insert into librarydb.bookqty(callNumber,bookQty,bookqtyOut) values (newcallNumber, 1,0);
            else
                update bookqty set bookQty = bookQty + 1 where callNumber = newCallNumber;
            end if;
        end$$

delimiter ;

Answer 1

一种选择是制作UPSERT。

DELIMITER //

CREATE PROCEDURE `intoBooksQty`(`newcallNumber` VARCHAR(10))
BEGIN
  INSERT INTO `bookqty` (`callNumber`, `bookQty`, `bookqtyOut`)
  SELECT `newcallNumber`, 1, 0
  FROM `books`
  WHERE `callNumber` = `newcallNumber`
    ON DUPLICATE KEY UPDATE `bookQty` = `bookQty` + 1;
END//

DELIMITER ;

SQL Fiddle demo

如果不存在并插入mysql存储过程

1 个答案: