#!/usr/bin/perl -wT

use strict;

my $searchstring = "aaaa OR bbbb OR cccc OR dddd";

$searchstring =~ s/(\w+) ?(OR|NOT|AND)/\(fieldname \= '$1'\) $2/g;

print "SELECT * FROM tablename WHERE $searchstring\n";


##</code><code>##

SELECT * FROM tablename WHERE (fieldname = 'aaaa') OR (fieldname = 'bbbb') OR (fieldname = 'cccc') OR dddd


##</code><code>##

SELECT * FROM tablename WHERE (fieldname = 'aaaa') OR (fieldname = 'bbbb') OR (fieldname = 'cccc') OR (fieldname =  'dddd')