Stefan Weiss <spaceman-4b9f8-20030703(at)ausgehaucht(dot)sensenmann(dot)at> writes:
> From <doc/html/sql-select.html>:
> | A CROSS JOIN or INNER JOIN is a simple Cartesian product, the same
> | as you get from listing the two items at the top level of FROM. CROSS
> | JOIN is equivalent to INNER JOIN ON (TRUE), that is, no rows are
> | removed by qualification.
> I thought that by using the second form, you would be able to do
> 'explicit' joins, effectivly telling the planner in which order to
> join multiple tables (in case you have to join 10+ tables)?
They are semantically equivalent, but not necessarily the same from a
performance point of view. The potential performance issues are covered
elsewhere; I think it would just obfuscate matters to try to include
that topic here.
regards, tom lane
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