Question

我需要通过表格中的表单提交行重新排序，具有以下嵌套页面布局结构

列：（表名为：sourcedocs3）

sort1 | sort2 | type

1 | 1 | parent

1 | 2 | child

2 | 1 | no nesting

3 | 1 | parent

3 | 2 | child

3 | 3 | child

4 | 1 | no nesting

我需要能够重新排序（通过PHP / Mysql）3到1而不会丢失基本结构 - 3变为1并且所有值为1的行都会递增）。听起来很简单，但我很难在洗牌后保持结构完好（3 | 1应该是1 | 1,3 | 2应该是1 | 2等）

Answer 1

START TRANSACTION;

UPDATE `why_do_people_never_give_the_table_name` SET sort1 = 999 
WHERE sort1 = 3;

UPDATE `why_do_people_never_give_the_table_name` SET sort1 = sort1 + 1 
WHERE sort1 BETWEEN 1 AND 3
ORDER BY sort1 DESC;

UPDATE `why_do_people_never_give_the_table_name` SET sort1 = 1 
WHERE sort1 = 999;

COMMIT;

请注意，如果您要将菜单移动到以后的位置，例如移动2到4，您需要按ASCending顺序订购第二个更新。

Answer 2

比尔的答案很明显 - 但是没有包含执行操作所需的PHP代码，所以这就是我最终的结果：

    <?php
//if new sort number is less than old sortnum
    if ($newsortnum < $oldsortnum){
         //RUN SEPARATE QUERIES
         $sql_rename="UPDATE  `sourcedocs` SET sort1 = '999' WHERE sort1 =".$oldsortnum." AND category =  '".$category."'";
         $sql_reorder="UPDATE  `sourcedocs` SET sort1 = sort1 +1 WHERE sort1 >= ".$newsortnum." AND sort1 <= ".$oldsortnum." AND category =  '".$category."'";
         $sql_insert="UPDATE  `sourcedocs` SET sort1 =".$newsortnum." WHERE sort1 = '999' AND category =  '".$category."'";
    }
    //if new sort number is greater than old sortnum decrement all sortnums greater than new sortnum and decrement sortnums between 
    if ($newsortnum > $oldsortnum){
    //RUN SEPARATE QUERIES
         $sql_rename="UPDATE  `sourcedocs` SET sort1 = '999' WHERE sort1 =".$oldsortnum." AND category =  '".$category."'";
         $sql_reorder="UPDATE  `sourcedocs` SET sort1 = sort1 -1 WHERE sort1 <= ".$newsortnum." AND sort1 >= ".$oldsortnum." AND category =  '".$category."'";
         $sql_insert="UPDATE  `sourcedocs` SET sort1 =".$newsortnum." WHERE sort1 = '999' AND category =  '".$category."'";
    }
    ?>

长话短说 - 我没有为beginTransaction（）创建一个PDO实例; ......有点乱，但它正在发挥作用。我可能会切换到PDO方法，但需要继续前进。如果您遇到类似的困难，这里是PDO信息的链接：

PHP.net - PDO Construct
PHP.net - PDO beginTransaction();

使用php重新排序父/子行mysql

2 个答案: