根据行获取数据

Question

我有tblControlFlag表，其数据如下。

我想编写一个查询，当

时输出为1

    RRO_FLAG=1 
AND SEAL_FLAG=1 
AND TEST_CODE='VLXXXXXX' 
AND SERIAL_NO='k7jpevdt'

如果任何Flag值不匹配，则查询返回空值。

直到现在，我已经尝试了Sub Query，但仍然无法实现结果。

那么这是可以实现的吗？

请帮帮我。谢谢

Answer 1

使用此查询

Select Case WHEN Count(*)>0 then 1 else null END AS TesColumn From tblControlFlag  when RRO_FLAG=1 AND SEAL_FLAG=1 AND TEST_CODE='VLXXXXXX' AND SERIAL_NO='k7jpevdt'

Answer 2

我不清楚您的问题。不确定要如何获得结果。

无论如何

在GROUP BY条件下使用HAVING()。这将返回符合条件的SERIAL_NO

select  SERIAL_NO
from    tblControlFlag
group by SERIAL_NO
HAVING   MAX(CASE WHEN FLAG_NAME = 'PRO_FLAG'  THEN FLAG_VALUE END) = '1'
AND      MAX(CASE WHEN FLAG_NAME = 'SEAL_FLAG' THEN FLAG_VALUE END) = '1'
AND      MAX(CASE WHEN FLAG_NAME = 'TESTCODE'  THEN FLAG_VALUE END) = 'VLXXXXXX'

或者如果您想要结果列1或0

select  SERIAL_NO,
        MATCH = CASE WHEN MAX(CASE WHEN FLAG_NAME = 'PRO_FLAG'  THEN FLAG_VALUE END) = '1'
                     AND  MAX(CASE WHEN FLAG_NAME = 'SEAL_FLAG' THEN FLAG_VALUE END) = '1'
                     AND  MAX(CASE WHEN FLAG_NAME = 'TESTCODE'  THEN FLAG_VALUE END) = 'VLXXXXXX'
                THEN  1
                ELSE  0
                END
from    tblControlFlag
group by SERIAL_NO

Answer 3

由于您尝试了子查询和EXISTS，因此这是非常简单的查询，但可能无法快速运行。

SELECT COUNT(DISTINCT SERIAL_NO)
FROM @tblControlFlag AS T1
WHERE EXISTS (SELECT * FROM @tblControlFlag T2 WHERE T1.SERIAL_NO = T2.SERIAL_NO AND T2.FLAG_NAME = 'RRO_FLAG' AND FLAG_VALUE = '1')
AND EXISTS (SELECT * FROM @tblControlFlag T2 WHERE T1.SERIAL_NO = T2.SERIAL_NO AND T2.FLAG_NAME = 'SEAL_FLAG' AND FLAG_VALUE = '1')
AND EXISTS (SELECT * FROM @tblControlFlag T2 WHERE T1.SERIAL_NO = T2.SERIAL_NO AND T2.FLAG_NAME = 'TEST_CODE' AND FLAG_VALUE = 'VLXXXXXX')

由于每个SERIAL_NO没有重复的FLAG_NAME，因此您可以将行转换为列并执行检查RRO_FLAG=1 AND SEAL_FLAG=1 AND TEST_CODE='VLXXXXXX' AND SERIAL_NO='k7jpevdt'

SELECT *
FROM (
    SELECT * FROM @tblControlFlag
) AS T
PIVOT (
    MAX(FLAG_VALUE) FOR FLAG_NAME IN (RRO_FLAG, [SEAL_FLAG], [TEST_CODE])
) AS P
WHERE RRO_FLAG=1 AND SEAL_FLAG=1 AND TEST_CODE='VLXXXXXX' AND SERIAL_NO='k7jpevdt'