Strange select query - Mailing list pgsql-general

From bobson@alpha.pl
Subject Strange select query
Date
Msg-id 3B9F26AE.17016.2067EF@localhost
Whole thread Raw
List pgsql-general
Hellow,

I notice wired behavior of backend,

for instance I've 3 tables TA, TB, TC with about 1k of records each,

and I do something like that:

select * from TA as a, TB as b, TC as c where
position('some text' in a.textfield)>0 or
(position('some text' in b.textfield)>0 and a.index=b.referencefield) or
(position('some text' in c.textfield)>0 and a.index=b.referencefield
and b.other_referencefield=c.index);

the backend start to execute query, but it seems to be 'never ending
story' because after 15 minutes of work I steel haven't result, and
backend still was eating my RAM. I know that this query is ugly and
bad, but I think backend will reject such query at parsing.

regards
Robert Partyka

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