SQL查詢從兩個表返回重複行

我試圖運行該SQL查詢選擇：SQL查詢從兩個表返回重複行

SELECT t.*, tu.*, t.contact_name as contact_name, 
t.contact_email as contact_email, t.ticketnumber as ticketnumber, 
t.subject as subject 
FROM tickets t, ticket_updates tu 
WHERE t.ticketnumber = tu.ticketnumber 
AND tu.type = 'update' AND tu.customer <> 'Y' 
AND t.status = 'Awaiting Customer' AND tu.datetime <= '2014-10-18 16:26:00' 
order by tu.datetime DESC LIMIT 0,5

它返回正確的結果，但在同一行

來源

2014-10-20 user3843997

它接縫門票和ticket_updates之間的關係是主從，所以如果你得到同樣的相同的結果，你可能在子表中相同的行。 – 2014-10-20 15:49:12

嘗試其顯示多個選擇DISTINCT：

SELECT DISTINCT t.*, tu.*...

或者你可以嘗試一個GROUP BY：

SELECT t.*, tu.*, t.contact_name as contact_name, t.contact_email as contact_email, 
t.ticketnumber as ticketnumber, t.subject as subject 
    FROM tickets t, ticket_updates tu 
    WHERE t.ticketnumber = tu.ticketnumber AND 
    tu.type = 'update' AND tu.customer <> 'Y' AND 
    t.status = 'Awaiting Customer' AND 
    tu.datetime <= '2014-10-18 16:26:00' 
    GROUP BY tu.`id` 
    order by tu.datetime DESC LIMIT 0,5

來源

2014-10-20 15:30:53 AnchovyLegend

使用DISTINCT仍返回在ticket_updates表相同 – user3843997 2014-10-20 15:32:31

有多個排在門票表 – user3843997 2014-10-20 15:32:57

每一行在這種情況下，'GROUP BY tu.id'應該工作 – AnchovyLegend 2014-10-20 15:37:36

爲了快速解決，您可以使用SELECT DISTINCT。通常，重複是數據庫和/或連接條件存在問題的提示。所以請確保表中沒有重複項，並且連接條件是正確的。

來源

2014-10-20 15:31:26 HoneyBadger

SQL查詢從兩個表返回重複行

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