在內部查詢中的外部查詢中使用結果

Question

我想做的是從數據庫中查詢所有唯一的區名稱，並在每個區名稱上獲取其對應的MIN和MAX ID 。

這是我現在所擁有的：

SELECT DISTINCT DISTRICTNAME, 
(SELECT MIN(`ID`)
    FROM [DATABASE_NAME]
        WHERE DISTRICTNAME = DISTRICTNAME) AS 'MIN', 
(SELECT MAX(`ID`) 
    FROM [DATABASE_NAME]
        WHERE DISTRICTNAME = DISTRICTNAME) AS 'MAX'
FROM [DATABASE_NAME]
WHERE [CONDITION]
ORDER BY DISTRICTNAME;

問題： MIN和MAX列顯示相同的值。 我不太確定內部查詢的WHERE子句。 我認為這就是問題所在。

救命？

Answer 1

使用GROUP BY子句嘗試此查詢

SELECT DISTRICTNAME, MIN(`ID`) AS 'MIN', MAX(`ID`) AS 'MAX'
FROM [DATABASE_NAME]
WHERE [CONDITION]
GROUP BY DISTRICTNAME
ORDER BY DISTRICTNAME;;