Question

我在SQL Server中有一个如下表：

DECLARE @tbl TABLE (val1 VARCHAR(10), val2 VARCHAR(10) )

INSERT INTO @tbl
VALUES ('x', 'a'), ('x', 'a'), ('p', 'b'), ('y', 'a'), ('p', 'b');

val1  |  val2
------+-------
x     |   a
x     |   a
p     |   b
y     |   a
p     |   b

结果应该是a（val2）的行，因为val1中a的值至少变为y一次。但是val2.b的行应该在结果中被忽略，因为它在val1中的值不会改变。

val1  |  val2
------+------
x     |   a
x     |   a
y     |   a

Answer 1

试试这个，

select t.*
from @tbl t
INNER JOIN (    select  t2.val2
                from @tbl t2
                group by t2.val2 
                having min(t2.val1) <> max(t2.val1)
            ) AS tt ON tt.val2 = t.val2

Answer 2

我终于使用如下所示了。

SELECT t.*
FROM @tbl t
WHERE EXISTS (
    SELECT t2.val2
    FROM @tbl t2
    WHERE t.val2 = t2.val2
    GROUP BY t2.val2
    HAVING min(t2.val1) <> max(t2.val1)
    )

Answer 3

这样做你想要的吗？

select t.*
from @tbl t
where t.val2 = (select t2.val2
                from @tbl t2
                group by t2.val2 
                having min(t2.val1) <> max(t2.val1)
               );

Answer 4

SELECT
    *
FROM @tbl
WHERE val2 IN
(
    SELECT
        Z.val2
    FROM
    (
        SELECT
            *,ROW_NUMBER() OVER(Partition BY val2 Order BY Val2) AS PartNo
        FROM     
        (
            SELECT 
                *   
            FROM @tbl 
            GROUP BY val1,val2
        )X
    )Z WHERE Z.PartNo>1
)

当一列的值至少对另一列值更改一次时，检索行

4 个答案: