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Re: Subselect with no records results in final empty set

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I always have a single row in these selects so the result will have only
a row.
I must make a single select for a framework that takes as parameter a
single select to complete a XML template in a particular situation.

------ Original Message ------
From: "John R Pierce" <pierce@xxxxxxxxxxxx>
To: pgsql-general@xxxxxxxxxxxxxx
Sent: 1/29/2015 10:52:25 PM
Subject: Re:  Subselect with no records results in final empty
set

On 1/29/2015 12:36 PM, Sterpu Victor wrote:

ON(null) never matched.

NULL is neither true nor false.

ON somefieldinthejoin IS NULL would be a valid syntax. except, that's
NOT a join condition, a join condition would be ON left_table.something
= right_table.something

ON (1=1)

equivalent to ON TRUE

but that will cross join everything, so if the left table has N rows
and the right table has M rows, you'll end up with N*M rows in the
result. is that really what you want ??




-- john r pierce 37N 122W
somewhere on the middle of the left coast



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