MYSQL：選擇/和/或兩個表

我試圖讓下面的SQL工作：MYSQL：選擇/和/或兩個表

SELECT * FROM tc_appointment as tcAppointment, tc_message as tcMessage 
WHERE tcAppointment.counsellor_id = 502 
AND 
(
    (tcAppointment.tc_message_id = tcMessage.id AND tcMessage.marked_read = false AND tcMessage.sender_id != 502) 
    OR 
    (tcAppointment.cancelled = true AND tcAppointment.cancelled_acknowledged = false) 
    OR 
    (tcAppointment.confirmed = false) 
);

的tcAppointment.tc_message_id是在表中唯一tc_appointment進入空。我試圖讓它返回爲counsellor_id = 502和第二OR statment是true

我似乎被卡住，因爲tc_message as tcMessage子句和第一AND/OR聲明的，但我不知道爲什麼。任何人都可以指出我正確的方向嗎？

來源

2015-09-02 Doahh

瞭解ANSI 92使用INNER，LEFT聯接和右聯接語法。 http://blog.codinghorror.com/a-visual-explanation-of-sql-joins/或者學習使用ANSI 92加入之前的外連接的概念。我相信符號是'* ='或'= *'，或者它是'+ ='和'= +'......我不記得了。 – xQbert

試着加入2個表，並使用 '去哪兒'：

SELECT * FROM tc_appointment as tcAppointment 
    LEFT JOIN tc_message as tcMessage 
    ON 
    ((tcAppointment.tc_message_id = tcMessage.id AND tcMessage.marked_read = false AND tcMessage.sender_id != 502) 
    OR 
     (tcAppointment.cancelled = true AND tcAppointment.cancelled_acknowledged = false) 
     OR 
     (tcAppointment.confirmed = false) 
) 

    WHERE tcAppointment.counsellor_id = 502

來源

2015-09-02 17:13:11 Tarek

MYSQL：選擇/和/或兩個表

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