语句:
SELECT *
FROM ACCOUNT A
WHERE
nvl(A.Acct_Totalized_Flag, 'N') = 'Y' -- ONLY Master Meters
AND EXISTS
(SELECT NULL -- There are new Read recs
FROM READ, Meter_Master, Meter -- for at least 1 sub mtr
WHERE Master_Meter_Num = A.Acct_Meter_Num ----changed by Allen
AND Master_Meter_ID = Meter_Master_ID
AND Meter_Number = Read_Meter
AND nvl(Process_Flag, 'N') = 'Y'
)
数据: 只列出关键字段 METER : METER_MASTER_ID Meter_Number
null SCPEDS23 ---此条已经满足上面的Acct_Totalized_Flag 的条件
1010 SCPEDS25
1010 SCPEDS26
Meter_Master:MASTER_METER_ID MASTER_METER_NUM
1010 SCPEDS23 上面的语句怎么能把SCPEDS23的信息取出来? 上面红色的部分不满足啊
SELECT *
FROM ACCOUNT A
WHERE
nvl(A.Acct_Totalized_Flag, 'N') = 'Y' -- ONLY Master Meters
AND EXISTS
(SELECT NULL -- There are new Read recs
FROM READ, Meter_Master, Meter -- for at least 1 sub mtr
WHERE Master_Meter_Num = A.Acct_Meter_Num ----changed by Allen
AND Master_Meter_ID = Meter_Master_ID
AND Meter_Number = Read_Meter
AND nvl(Process_Flag, 'N') = 'Y'
)
数据: 只列出关键字段 METER : METER_MASTER_ID Meter_Number
null SCPEDS23 ---此条已经满足上面的Acct_Totalized_Flag 的条件
1010 SCPEDS25
1010 SCPEDS26
Meter_Master:MASTER_METER_ID MASTER_METER_NUM
1010 SCPEDS23 上面的语句怎么能把SCPEDS23的信息取出来? 上面红色的部分不满足啊
而Meter_Master表中的id是1010为什么有这个Master_Meter_ID = Meter_Master_ID 条件,还是能取得id为null的记录