How can I call a function to return a code fragement from within a pg_Exec

Original.. This works, but needs calls to three tables. Where 'code' actually
holds all required info.
$result = pg_Exec($database,"select code,title,price from catalog where (
title like '%$keyword%' and category like '$category' and language like
'$language') order by code");

What I want to do, is just extract the records, that match the code, broken
down into category, and language.
$result = pg_Exec($database,"select code,title,price from catalog where (
title like '%$keyword%' and (foo($regs[1])) == '$category' and
(foo($regs[2])== '$language') order by code");
...................................................................
The foo() function is a call to an egreg thing,
(ereg( "([0-9]{1,2})([A-Za-z]{1,3})(.*)", $t_code, $regs );)
which can return what I'm looking for,

I know these error messages are complaining about foo() being in the statement,
which is what I'm trying to solve.
Warning: PostgresSQL query failed: ERROR: No such function 'foo' with the
specified attributes in
/usr/local/apache/share/htdocs/php/book-2.php3 on line 120
Warning: 0 is not a PostgresSQL result index in
/usr/local/apache/share/htdocs/php/book-2.php3 on line
121

Thanks for any clues to this connundrum...

Robert

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