NAME

Sort::SQL - manipulate SQL sort strings

SYNOPSIS

  use Sort::SQL;
  
  my $array = Sort::SQL->string2array('foo ASC bar DESC bing');
  # $array == [ { 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 one method: string2array().

string2array( sql sort string )

Takes a scalar string of the SQL ORDER BY syntax and turns it into an array of key/value pair hashrefs.

I use this method frequently in my Template Toolkit applications, where I want to be able to create re-sortable table columns. I presume there are many other uses.

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->string2array( $sort_order );
 

And then in my template:

 column.links = {};
 
 FOREACH pair IN search.order;

  column     = pair.each.0;
  direction  = pair.each.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.