我只希望查看列'Stadt'(= City)不等於'Hauptstadt'(= Capital)的行。 我的表如下所示:MYSQL:SELECT DISTINCT只顯示唯一的行
+----------------------+-------------------+--------------------------+---------------+
| Name | Stadt | Land | Hauptstadt |
+----------------------+-------------------+--------------------------+---------------+
| Kunstmuseum | Bern | Schweiz | Bern |
| Musée Picasso | Paris | Frankreich | Paris |
| Museum Ludwig | Köln | Deutschland | Berlin |
| Museum of Modern Art | New York | United States of America | Washington DC |
| Städel | Frankfurt am Main | Deutschland | Berlin |
+----------------------+-------------------+--------------------------+---------------+
我只是想看看(期望輸出):
+----------------------+-------------------+--------------------------+---------------+
| Name | Stadt | Land | Hauptstadt |
+----------------------+-------------------+--------------------------+---------------+
| Museum Ludwig | Köln | Deutschland | Berlin |
| Museum of Modern Art | New York | United States of America | Washington DC |
| Städel | Frankfurt am Main | Deutschland | Berlin |
+----------------------+-------------------+--------------------------+---------------+
我試了一下這個:
SELECT DISTINCT Name, Stadt, Land ,Hauptstadt
FROM Museum
GROUP BY 'Name', 'Stadt', 'Land', 'Hauptstadt'
ORDER BY Name;
輸出:
+----------------------+----------+--------------------------+---------------+
| Name | Stadt | Land | Hauptstadt |
+----------------------+----------+--------------------------+---------------+
| Museum of Modern Art | New York | United States of America | Washington DC |
+----------------------+----------+--------------------------+---------------+
我的SELECT應該如何得到我想要的輸出?
感謝您的幫助!
爲什麼你需要'DISTINCT'只是比較兩列?你的要求聽起來像'Stadt <> Hauptstadt' ... –
只是你知道未來; DISTINCT是一個函數,所以如果你使用它,語法應該是DISTINCT(some_col)。根據你的標準,你應該接受Gordon的答案。 – user3741598
'DISTINCT'不是**函數,根據[規範](http://dev.mysql.com/doc/refman/5.1/en/select.html),沒有括號:'SELECT [ALL | DISTINCT | DISTINCTROW] ...'。您可以使用圓括號,但是「DISTINCT」仍然會影響所有選定的列,因此會造成混淆。 –