在mysql中運行月份邏輯

Question

我有一個包含兩列col_a和col_b的表。我應該在下面的圖像中看到它的價值。我們怎麼能得到這個。

Answer 1

set @month = 3; 
select t.month, s.month from 
(
select 1 mns, 'Jan' month union select 2,'Feb' union select 3,'Mar' union 
select 4,'Apr' union select 5,'May' union select 6,'Jun' union 
select 7,'Jul' union select 7,'Aug' union select 9,'Sep' union 
select 10,'Oct' union select 11,'Nov' union select 12,'Dec' 
) s 
, 
(
select 1 mnt, 'Jan' month union select 2,'Feb' union select 3,'Mar' union 
select 4,'Apr' union select 5,'May' union select 6,'Jun' union 
select 7,'Jul' union select 7,'Aug' union select 9,'Sep' union 
select 10,'Oct' union select 11,'Nov' union select 12,'Dec' 
) t 
where t.mnt <= s.mns and t.mnt <= @month