Re: Functional Indexes

The two functions do not group data the same way, so a common index is not 
possible.
urlhost would put pgsql.org and pgsql.com close together.
urltld would but pgsql.com and xyz.com close together.

Frank


At 01:36 PM 7/15/03, David Olbersen wrote:

>Hello all,
>
>I have a function (urlhost) which finds the 'host' portion of a URL. In 
>the case of http://www.foobar.com/really/long/path/to/a/file it returns 
>"www.foobar.com".
>
>I also have a function (urltld) which returns the TLD of a URL. In the 
>case of http://www.foobar.com/really/long/path/to/a/file it returns ".com" 
>(the leading dot is OK).
>
>urltld uses urlhost to do it's job (how should be apparent).
>
>Now the question: is there a single index I can create that will be used 
>when my  WHERE clause contains either urlhost or urltld? I could create 
>two functional indexes, but that seems a bit silly to me.
>
>Any thoughts?
>
>--------------------------
>David Olbersen
>iGuard Engineer
>St. Bernard Software
>11415 West Bernardo Court
>San Diego, CA 92127
>1-858-676-2277 x2152
>
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