在循环中使用IF语句MYSQL

Question

我想为MySQL创建一个存储例程,用于计算一个月的业务或工作日数(工作日为周一至周五).

这是语法错误,但我不知道语法错误是什么.它告诉我的全部是:

1064 - 您的SQL语法出错; 查看与您的MySQL服务器版本对应的手册,以便在'WHILE(@ daycount <@totaldays)附近使用正确的语法DO IF(WEEKDAY(@checkweekday)<6)THEN'在第2行

我的语法错误如下:

    WHILE(@daycount < @totaldays) DO
          IF (WEEKDAY(@checkweekday) < 6) THEN

我的代码:

      SELECT MONTH(CURDATE()) INTO @curmonth;
      SELECT MONTHNAME(CURDATE()) INTO @curmonthname;
      SELECT DAY(LAST_DAY(CURDATE())) INTO @totaldays;
      SELECT FIRST_DAY(CURDATE()) INTO @checkweekday;
      SELECT DAY(@checkweekday) INTO @checkday;
      SET @daycount = 0;
      SET @workdays = 0;

    BEGIN
      WHILE(@daycount < @totaldays) DO
          IF (WEEKDAY(@checkweekday) < 6) THEN
            SET @workdays = @workdays+1;
          END IF;
          SET @daycount = @daycount+1;
          SELECT ADDDATE('@checkweekday', INTERVAL 1 DAY) INTO @checkweekday;
      END WHILE;
    END;
    SELECT @workdays;

有人能够提供帮助吗？

更新 我收到与以下代码相同的错误,所以它可能与此有关:

    SET @workdays = 0;
    IF (WEEKDAY('2013-06-13') < 6) THEN
      SET @workdays = @workdays+1;
    END IF;
    SELECT @workdays;

Answer 1

I have discovered that you cannot have conditionals outside of the stored procedure in mysql. This is why the syntax error. As soon as I put the code that I needed between

   BEGIN
   SELECT MONTH(CURDATE()) INTO @curmonth;
   SELECT MONTHNAME(CURDATE()) INTO @curmonthname;
   SELECT DAY(LAST_DAY(CURDATE())) INTO @totaldays;
   SELECT FIRST_DAY(CURDATE()) INTO @checkweekday;
   SELECT DAY(@checkweekday) INTO @checkday;
   SET @daycount = 0;
   SET @workdays = 0;

     WHILE(@daycount < @totaldays) DO
       IF (WEEKDAY(@checkweekday) < 5) THEN
         SET @workdays = @workdays+1;
       END IF;
       SET @daycount = @daycount+1;
       SELECT ADDDATE(@checkweekday, INTERVAL 1 DAY) INTO @checkweekday;
     END WHILE;
   END

Just for others:

If you are not sure how to create a routine in phpmyadmin you can put this in the SQL query

    delimiter ;;
    drop procedure if exists test2;;
    create procedure test2()
    begin
    select ‘Hello World’;
    end
    ;;

运行查询.这将创建一个名为test2的存储过程或存储例程.现在转到例程选项卡并编辑存储过程以使其成为您想要的.如果您从存储过程开始,我还建议您阅读http://net.tutsplus.com/tutorials/an-introduction-to-stored-procedures/.

你需要的first_day函数是: 如何获取mysql中每个相应月份的第一天？

显示过程正常工作 只需在END WHILE和END END下面添加以下行

    SELECT @curmonth,@curmonthname,@totaldays,@daycount,@workdays,@checkweekday,@checkday;

然后在SQL查询窗口中使用以下代码.

    call test2 /* or whatever you changed the name of the stored procedure to */

注意:如果您使用此请注意,此代码不会考虑到国家观察到的假期(或任何假期).