MySQL查询在单个查询中将多个列排序在一起
要对多列进行排序，请使用ORDERBYGREATEST()。让我们首先创建一个-
mysql> create table DemoTable1395 -> ( -> Value1 int, -> Value2 int, -> Value3 int -> );
使用insert在表中插入一些记录-
mysql> insert into DemoTable1395 values(40,50,60); mysql> insert into DemoTable1395 values(90,56,80); mysql> insert into DemoTable1395 values(10,20,30);
使用选择显示表中的所有记录-
mysql> select * from DemoTable1395;
这将产生以下输出-
+--------+--------+--------+ | Value1 | Value2 | Value3 | +--------+--------+--------+ | 40 | 50 | 60 | | 90 | 56 | 80 | | 10 | 20 | 30 | +--------+--------+--------+ 3 rows in set (0.00 sec)
这是对多列进行排序的查询-
mysql> select * from DemoTable1395
-> order by greatest(Value1,Value2,Value3);这将产生以下输出-
+--------+--------+--------+ | Value1 | Value2 | Value3 | +--------+--------+--------+ | 10 | 20 | 30 | | 40 | 50 | 60 | | 90 | 56 | 80 | +--------+--------+--------+ 3 rows in set (0.00 sec)