MySQL不同的總和，按

Question

這是我的桌子：

id  user_id   type   value

1   1         type1     2
2   2         type1     1
3   1         type2     5
4   1         type1     2

我想要這樣的輸出：

  user_id   type1   type2
    1         4     5
    2         1     0

請幫忙

Answer 1

您可以這樣嘗試：

SELECT 
    user_id, 
    sum( if( type = 'type1', value, 0 ) ) AS type1,  
    sum( if( type = 'type2', value, 0 ) ) AS type2
FROM 
    table_name 
GROUP BY 
    user_id;

Answer 2

我想，這就是您要搜索的內容：

select 
   user_id,
   (select sum(value) from <yourtablename> sub1 where type = 'type1' where sub1.user_id = baseTable.user_id) as type1,
   (select sum(value) from <yourtablename> sub2 where type = 'type2' where sub2.user_id = baseTable.user_id) as type2,
from
   <yourtablename> baseTable