MySQL查詢：使用UNION和獲得的行號SELECT

Question

的一部分，我有一個聯合查詢，如下所示：

 
(SELECT t.id, t.name, c.company AS owner, t.creation_date AS date, t.notes 
FROM tool t, client c 
WHERE t.id_customer = '15' AND t.trash_flag = '1') 
    UNION 
(SELECT f.id, f.name, CONCAT(m.first_name, ' ', m.last_name) AS owner, f.date, f.notes 
FROM file f, meta m 
WHERE ((f.acl = 0) OR (f.acl = 1 AND '1' = TRUE) OR (f.acl = 2 AND f.id = '7')) AND f.id = '15' AND f.trash_flag = '1' AND m.user_id = f.id_user) 
ORDER BY 'name' 'ASC' LIMIT 0,20 

一切工作正常，但我有兩個問題：

1. 如何添加一列到整個結果集，給出行號
2. 我可以做到這一點，而不使用UNION例如高級加入？

感謝您的時間MySQL專家！

Answer 1

我不能測試它現在右擊但我發現，以下可能的工作：

參考：Row Number Variable

SQL語句

SELECT @rownum := @rownum + 1 rownum 
     , t.* 
FROM (
      (SELECT t.id 
        , t.name 
        , c.company AS owner 
        , t.creation_date AS date 
        , t.notes 
      FROM tool t 
        , client c 
      WHERE t.id_customer = '15' 
        AND t.trash_flag = '1' 
      ) UNION (
      SELECT f.id 
        , f.name 
        , CONCAT(m.first_name, ' ', m.last_name) AS owner 
        , f.date 
        , f.notes 
      FROM file f 
        , meta m 
      WHERE ((f.acl = 0) OR (f.acl = 1 AND '1' = TRUE) OR (f.acl = 2 AND f.id = '7')) AND f.id = '15' AND f.trash_flag = '1' AND m.user_id = f.id_user) 
      ) 
     ) t 
     , (SELECT @rownum := 0) r 
ORDER BY 
     'name' ASC 
LIMIT 0, 20