這個MySQL查詢的語法有什麼問題？

Question

我有一個非常簡單的MySQL查詢：

(SELECT 
    id 
    , creation_date AS date 
    , 'order' AS type 
    FROM bus_orders 
    WHERE 1 
UNION ALL SELECT 
    id 
    , start_date AS date 
    , 'contract start' AS type 
    FROM bus_contracts 
    WHERE 1 
UNION ALL SELECT 
    id 
    , end_date AS date 
    , 'contract end' AS type 
    FROM bus_contracts 
    WHERE 1 
) ORDER BY date DESC LIMIT 5 

運行它不過是給我的語法錯誤：

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNION ALL SELECT id, start_date AS date, 'contract start' AS type FROM bus_contr' at line 1

我敢肯定，這是顯而易見的事情，但我不能很圖出來。任何人都可以發現我在這裏做錯了嗎？

Answer 1

除去WHERE 1或更改爲WHERE 1=1

SELECT * 
FROM 
    (
     SELECT id , creation_date AS date , 'order' AS type 
     FROM bus_orders 
     UNION ALL 
     SELECT id , start_date AS date , 'contract start' AS type 
     FROM bus_contracts 
     UNION ALL 
     SELECT id , end_date AS date , 'contract end' AS type 
     FROM bus_contracts 
    ) x 
ORDER BY date DESC 
LIMIT 5 

Answer 2

您有領先的)需要刪除。