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Re: join condition against where with coalesce

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I figured out my problem.
Table1 and Table2 have matches for every pk,fk just not on typeid=14,
therefore when I join on just the pk,fk and do a where looking for null, it
doesn't find any rows that qualify.

Doesn't help me solve my problem, but at least I know where I'm at.

Sim

Sim Zacks wrote:
Should there be any difference between:

select * from table1 a left join table2 b on a.pk=b.fk and b.typeid=14
and
select * from table1 a left join table2 b on a.pk=b.fk
where coalesce(b.typeid,14)=14

The reason I need to use the coalesce is because my goal is to do it with a full join and can't use
the and condition because it is not merge-joinable.

My test with the left join showed me that with the where it doesn't give any results, while I would expect it to give me all the results in the first table.

Any thoughts?


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