如何設置標誌在SQL查詢中

Question

我的查詢：

CREATE OR REPLACE VIEW Basic 
AS 
SELECT id FROM my_post 
UNION 
SELECT id FROM scrap_post 

如果該行是從my_post那麼我想設置的標誌p，否則s。

Answer 1

一個硬編碼值添加

CREATE OR REPLACE VIEW Basic 
AS 
select id,'p' as flag from my_post 
UNION 
select id,'s' from scrap_post 

注：如果你不關心結果重複然後更改UNION到UNION ALL其運行速度更快