如何按自定义字段对MySQL ResultSet进行排序？

Question

以下是架构和数据：

Create table tblTestSorting (col int);
INSERT INTO tblTestSorting VALUES(2), (5), (3), (6), (4), (7), (1)

我有这样的查询：

SELECT col, 5-col AS 'extra' FROM tblTestSorting ORDER BY 'extra';

我希望将结果排序为＆＃39; extra＆＃39;专栏，但是 此查询不会向我提供按＆＃39;额外＆＃39;排序的结果柱..

如何实现这个...... ??

Answer 1

试试这个：

SELECT col, (5 - col) AS extra
FROM tblTestSorting 
ORDER BY extra;

检查SQL FIDDLE DEMO

<强>输出

| COL | EXTRA |
|-----|-------|
|   7 |    -2 |
|   6 |    -1 |
|   5 |     0 |
|   4 |     1 |
|   3 |     2 |
|   2 |     3 |
|   1 |     4 |

Answer 2

按类型（asc或desc）给出订单.. 试试这个..

SELECT col, 5-col AS extra FROM tblTestSorting ORDER BY col ASC

Answer 3

两种方式

SELECT col, 5-col AS 'extra' FROM tblTestSorting ORDER BY 5-col;


SELECT col, 5-col AS 'extra' FROM tblTestSorting ORDER BY 2;

Answer 4

试试这个：

 SELECT col, 5-col AS 'extra' FROM tblTestSorting ORDER BY 'extra' ASC

或

 SELECT * FROM (SELECT col, 5-col AS 'extra' FROM tblTestSorting) as t ORDER BY t.'extra' ASC

Answer 5

解决方案1 ​​

  

选择*来自（SELECT col，5-col AS'额外'FROM tblTemp）订单额外

或解决方案2

  

SELECT col，5-col AS`extra` FROM tblTemp order by“extra`