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如题: mysql 的数据结构 如下
查询 A B C 三列中的最大值 目前已经有一条sql 可以实现了 想问各位 还可以有其他更好的idea吗..
select id,a,b,c,(a+((b+c+abs(b-c))/2)+abs(a-(b+c+abs(b-c))/2))/2 from test;
补充 下午 跟别人 又 学到了一个 greatest 函数
greatest
select id,a,b,c,greatest(a,b,c) as max from XXX
光阴似箭催人老,日月如移越少年。
mysql> set @a = 5, @b = 6, @c = 11; Query OK, 0 rows affected (0.00 sec) mysql> select if(@a > @b, if(@a > @c, @a, @c), if(@b > @c, @b, @c)) max; +------+ | max | +------+ | 11 | +------+ 1 row in set (0.00 sec)
select greatest(a,b,c) max from table_name
.. 查出来 程序处理不行吗?
select greatest(a,b,c) max from table_name
.. 查出来 程序处理不行吗?