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Regular Expression Interconnection

I have an inner join on regular expressions - it is very slow. Is there an easy way to speed this up? I am using postgres.

FROM A
inner join B ON trim(lower(replace(replace(replace(B.enginequery,',',' '),'"',' '),'+',' '))) = trim(lower(A.keyphrase))
             OR trim(lower(replace(replace(replace(B.enginequery,',',' '),'"',' '),'+',' '))) ~ (trim(lower(A.keyphrase)) || '$')
             OR trim(lower(replace(replace(replace(B.enginequery,',',' '),'"',' '),'+',' '))) ~ (trim(lower(A.keyphrase)) || ' ')
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Is there an easy way to speed this up?

The reason for performance is all operations, not to mention regular expressions, which must be performed only in order to make a match. You need to simplify the relationship so that it does not need to be performed.

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I would start by posting the results:

 trim (lower (replace (replace (replace (B.enginequery, ',', ''), '"', ''), '+', '')))

. , . postgres, . Ms sql server , B.enginequery .

, , .

+1

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