NAME

Sort::SQL - manipulate SQL sort strings

SYNOPSIS

            

              
              
use Sort::SQL;
my $array_of_arrays = Sort::SQL->parse('foo ASC bar DESC bing');
# $array_of_arrays == [ [ 'foo', 'ASC' ], [ 'bar', 'DESC' ], [ 'bing', 'ASC' ] ]
my $array_of_hashes = Sort::SQL->string2array('foo asc bar DESC bing');
# $array_of_hashes == [ { foo => 'ASC' }, { bar => 'DESC' }, { bing  => 'ASC' } ]
            
          

DESCRIPTION

Sort::SQL is so simple it almost doesn't deserve to be on CPAN. But since I kept finding myself copy/pasting this method into multiple places, I finally figured it deserved to live in its own class.

METHODS

Sort::SQL implements these methods, each of which take a scalar string of the SQL ORDER BY syntax and return a data structure.

parse( sql sort string )

Returns sql sort string as an arrayref of arrayrefs.

string2array( sql sort string )

Returns sql sort string as an arrayref of hashrefs. This is for backwards compat only -- parse() is a little faster and more usable.

EXAMPLE

Here's how I use it in my web applications. I want to allow users to re-sort search results by table column header. Each column name is a link back to the server, and I want to provide the SQL ORDER BY value as a param in the URI.

In my controller code I do:

            

              
              
my $sort_order = $c->request->param('order');
$c->stash->{search}->{order} = Sort::SQL->parse( $sort_order );
            
          

And then in my template:

            

              
              
column.links = {};
FOREACH pair IN search.order;
 column     = pair.0;
 direction  = pair.1;
 # toggle the sort direction for current sorted column
 # so the next browser request will reverse the sort
 IF ( direction == 'ASC' );
   column.links.$column.direction = 'DESC';
 ELSE;
   column.links.$column.direction = 'ASC';
  
 END;
END;
            
          

SEE ALSO

SWISH::API::Object

AUTHOR

Peter Karman, <perl@peknet.com>

Thanks to Atomic Learning for sponsoring the development of this module.

COPYRIGHT AND LICENSE

Copyright (C) 2007 by Peter Karman

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.7 or, at your option, any later version of Perl 5 you may have available.