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List:       postgresql-general
Subject:    Re: [GENERAL] Determining if "in a text set"
From:       Charles Tassell <ctassell () isn ! net>
Date:       1999-03-28 6:56:58
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What about constructing your SQL query using a bunch of OR's?  IE:
SELECT * FROM table WHERE day = 'MON' or day = 'TUE' ....
My memory of SQL syntax is woefully blurry (been a while, just getting back
into it) but this should work.  That way you do the strtok stuff once (you
should never use strtok, strtok is evil, in the bad way) and only end up
with one query containing all your records.


At 12:41 AM 3/27/99, Richi Plana wrote:
>Hi,
>
>I have a table/class with a text field which contains a single word
>(possibly trailed by whitespaces). Given a phrase (a text literal composed
>of words separated by one or more whitespaces), what's the best way to
>SELECT those tuples with fields containing instances that match exactly
>one of the words in the given string?
>
>Example:
>
>Table:
>Tuple#   ...   FieldN
>1        ...   'MON'
>2        ...   'TUE'
>3        ...   'THURS'
>4        ...   'THU'
>5        ...   'FRI'
>
>Given phrase:
>'MON TUE WED THURS'
>Tuple 1 will match
>Tuple 2 will match
>Tuple 3 will match
>Tuple 4 will NOT match
>Tuple 5 will NOT match
>
>Right now, I'm extracting (using strtok(), 8^P) each word from the given
>phrase and using "SELECT * FROM {class} where FieldN LIKE '%{word}%'", but
>it's terribly slow, relies on strtok() to parse words, and Tuple 4 above
>will match.
>
>
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