Re: EXISTS vs IN vs OUTER JOINS - Mailing list pgsql-performance

Tomasz,

> I read your mail once again, but I still don't understand what are
> you
> talking about.
> I'll write example - maybe it will help us to understand each other.

Hmmm ... you're right.  Sorry for being dense.  It shouldn't work, but
it does.

Tom, Bruce:

If I run the query:

SELECT t1.*
FROM table1 t1
  LEFT JOIN table2 t2 ON t1.xid = t2.xid
WHERE t2.label IS NULL

I will get rows in t1 for which there is no row in t2.  This does not
seem SQL-spec to me; shouldn't I get only rows from t1 where a row
exists in t2 and t2.label IS NULL?

-Josh