sql-server - 尝试仅将唯一行插入新表

Question

我正在尝试仅将唯一值插入表中，但它不起作用。对于所有 6000 行，Securities 表中只有一个 LastDownload 值。但在我的查询中，我在@Temp 中得到了超过 6000 个重复值。我只想要一个值。我错过了什么？

DECLARE @Temp TABLE ( Info VARCHAR( 256 ) )

INSERT INTO @Temp
SELECT LastDownLoad
FROM Securities AS S
WHERE NOT EXISTS( SELECT * FROM @Temp AS T WHERE T.Info = S.LastDownLoad ) 

Answer 1

也许这过于简单了……但是……它似乎适合……

DECLARE @Temp TABLE ( Info VARCHAR( 256 ) )

    INSERT INTO @Temp
    SELECT Distinct LastDownLoad
    FROM Securities

Answer 2

将两个答案放在一起，您将得到完整的答案：

DECLARE @Temp TABLE ( Info VARCHAR( 256 ) )

INSERT INTO @Temp
SELECT DISTINCT LastDownLoad
FROM Securities AS S
WHERE NOT EXISTS( SELECT * FROM @Temp AS T WHERE T.Info = S.LastDownLoad ) 

Answer 3

你试过用distinct吗？

DECLARE @Temp TABLE ( Info VARCHAR( 256 ) )

INSERT INTO @Temp
SELECT LastDownLoad
FROM Securities AS S
WHERE NOT EXISTS( SELECT DISTINCT * FROM @Temp AS T WHERE T.Info = S.LastDownLoad )