我只想從我的數據庫中選擇最新的輸入。SQL - 在NVARCHAR列中選擇最新的最大日期
目前,它總是給我,即使我使用的查詢
SELECT
A.[Id],
UD.[Name],
MAX(CONVERT(DATE, AN.[PostedOn])) 'date',
CAST(AN.[Content] AS NVARCHAR(MAX)) 'comment'
FROM
[dbo].[Account] A
LEFT JOIN
[dbo].[UserData] UD ON A.[UserId] = UD.UserId
LEFT JOIN
[dbo].[Note] AN ON UD.[UserId] = AN.[CustomerID]
GROUP BY
A.[Id], UD.[Name], CAST(AN.[Content] AS NVARCHAR(MAX))
當前結果
+---------+------------------------+------------+-------+
|id |Name |Date |Comment|
+---------+------------------------+------------+-------+
|01 |John |2017-08-15 |Blue |
|01 |John |2017-07-10 |Green |
|02 |Bob |2017-07-15 |Green |
|02 |Bob |2017-06-05 |Red |
|03 |Eric |2017-08-15 |Yellow |
|04 |Karl |2017-08-15 |NULL |
|04 |Karl |2017-06-10 |Black |
+---------+------------------------+------------+-------+
預期/所需結果的最大
簡體版過濾所有評論:
+---------+------------------------+------------+-------+
|id |Name |Date |Comment|
+---------+------------------------+------------+-------+
|01 |John |2017-08-15 |Blue |
|02 |Bob |2017-07-15 |Green |
|03 |Eric |2017-08-15 |Yellow |
|04 |Karl |2017-08-15 |NULL |
+---------+------------------------+------------+-------+
FYI如果我從查詢中刪除CAST(AN.[Content] AS NVARCHAR(MAX)) 'comment'
,然後我看不出「重複」名稱/標識了(但當時沒有發表評論)
任何想法?
標記您正在使用的dbms,有些產品細節... – jarlh