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From "Mccollough, Michael" <Michael.McCollo...@emc.com>
Subject Inaccurate query results
Date Wed, 28 Jan 2015 19:03:11 GMT
I have a simple database, two tables

DISTROGROUP and RECIPIENTS, each have the field DG_ID and this field is indexed

I have 86,795 rows in DISTROGROUP
I have 230,823 rows in RECIPIENTS

I am using the table to migrate items. I have processed almost all of them except ones where
I have a DISTROGROUP.LOAD_STATUS is NULL, these should be rows where there is a distribution
group but no recipients.

The query I used to process is select DG_ID, col2, col3, etc from DISTROGROUP where LOAD_STATUS
is NULL and DG_ID in (select DG_ID from RECIPIENTS). This returns 0 results
However, I can take one of the rows from DISTROGROUP that has a LOAD_STATUS = NULL, and I
CAN match up the DG_ID to a DG_ID in RECIPIENTS so why don't I get results in the original
query? I would use a NOT IN query to separate out actual DISTROGROUP rows with no match, but
I waited over 15 minutes for the NOT IN query before giving up on it.

Any help/guidance is appreciated.

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