Re: from_collapse_limit considerations

Started by Tom Laneover 11 years ago2 messages
#1Tom Lane
tgl@sss.pgh.pa.us

Antonin Houska <ah@cybertec.at> writes:

I noticed that - unlike join_collapse_limit - the from_collapse_limit does not
enforce maximum length of the top-level list. Shouldn't it do?

How would it do that? You want it to fail outright if there are more than
N tables? That seems unhelpful.

Also, the order of FROM-list items seems to affect the way RTEs are grouped
into (sub)lists.

Yeah.

regards, tom lane

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#2Antonin Houska
ah@cybertec.at
In reply to: Tom Lane (#1)

[ I think I responded earlier but don't see my mail in the archive... ]

Tom Lane <tgl@sss.pgh.pa.us> wrote:

Antonin Houska <ah@cybertec.at> writes:

I noticed that - unlike join_collapse_limit - the from_collapse_limit does not
enforce maximum length of the top-level list. Shouldn't it do?

How would it do that? You want it to fail outright if there are more than
N tables? That seems unhelpful.

Sure, truncation of the FROM list would be crazy, and that's not what I tried to propose.

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Antonin Houska
Cybertec Schönig & Schönig GmbH
Gröhrmühlgasse 26
A-2700 Wiener Neustadt
Web: http://www.postgresql-support.de, http://www.cybertec.at

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