mysql从多选中选择最低价格

Question

表格价格

user_id    b01    b02    b03    b04    b05    b06    b07    b08    b09
MP01       21     32     12     34     56     26     21     21     26    
MO11       81     332    112    1      12     22     71     17     23  

如何从价格中选择最低价格WHERE user_id ='MP01'？

user_id MP01的示例，以获得结果12

Answer 1

根据你的例子，我认为你的意思是结果是12.如果是这样你可以做

SELECT LEAST(b01, b02, b03, b04, b05, b06, b07, b08, b09) FROM price WHERE user_id = 'MP01'

Answer 2

这是LEAST的替代方法。使用最少功能并不容易。但在某些情况下可能派上用场

SELECT MIN(b01) FROM(
select user_id , b01 from price
union all
select user_id , b02 from price
union all
select user_id , b03 from price
union all
select user_id , b04 from price
union all
select user_id , b05 from price
union all
select user_id , b06 from price
union all
select user_id , b07 from price
union all
select user_id , b08 from price
union all
select user_id , b09 from price
) temp 
WHERE user_id = 'MP01'

Answer 3

您可以使用least

select least(b01,b02,b03,b04,b05,b06,b07,b08,b09)
FROM Table1
where user_id='MP01'

Answer 4

您可以使用LEAST功能，如：

select least(b01,b02,b03,b04,b05,b06,b07,b08,b09) from price where user_id = 'MP01'

http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html#function_least