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Thanks for help with this one
I have 2 tables
DATA_STANDARD with columns ID and VALUE
and
DATA_EXTRA with column DS_ID and EXTRA_VALUE
The idea is that extra information is stored in the DATA_EXTRA table when required.
How do I select all values from DATA_STANDARD where there is either no entry in DATA_EXTRA or EXTRA_VALUE is zero.
something like this?
select ds.id from DATA_STANDARD ds, DATA_EXTRA de
where
( ds.id not in ( select DS_ID from DATA_EXTRA ) )
or
(
--Join
( ds.id = de.DS_ID )
and
( de.extra_value is null )
)
Why is this wrong?
Thanks Received on Thu Jan 29 2004 - 05:17:45 CST