技術標籤：資料庫mysqlsql

今天無聊去看部落格問答，看見了行轉列的問題，就動手解決下，牢固牢固

自己建的示例表如下

sql如下
這裡用到ifnull函式把為空的值程式設計0，寫的不好勿噴哈哈哈哈

SELECT DISTINCT  c.name,  
IFNULL((SELECT COALESCE(1,null) FROM b  WHERE tab = 1 and name = c.name ) ,0)AS '早餐' ,
IFNULL((SELECT COALESCE(1,null) FROM b  WHERE tab = 2 and name = c.name ),0) AS '中餐'
 
 ,
IFNULL((SELECT COALESCE(1,null) FROM b  WHERE tab = 3 and name = c.name ) ,0) AS '晚餐'
FROM b c 

結果如下