Re: [Openinteract-help] Queries with functions

[Chris W. <ch...@cw...>]

On Mar 26, 2004, at 10:15 AM, Vsevolod (Simon) Ilyushchenko wrote:
> Maybe I am missing something, but is there a way in SPOPS to retrieve 
> expressions like MAX(field) etc. I'd like to be able to say something 
> like
> my ($maxValue) = SPOPS::Class->select({select => [MAX(field)]})
>
> (ie, keeping the SPOPS way of passing parameters compared to raw SQL 
> calls).
>
> It sounds simple, but I can't find a way of doing it.

Every SPOPS::DBI implementation also subclasses SPOPS::SQLInterface, so 
you can do:

  my $max_row = SPOPS_Class->db_select({
                           field  => [ 'MAX( myfield )' ],
						  table  => SPOPS_class->table_name,
						  return => 'single' );
  print "Max of 'myfield' is $max_row->[0]\n";

I always put stuff like this in the class implementation so I can just 
do something like:

  my $max = SPOPS_Class->find_max_myfield;

Of course you can parameterize further, passing in 'myfield' and 
plugging it into the select; even just creating a find_max() in a 
parent class of all your SPOPS classes since this isn't tied to any 
particular class.

Later,

Chris

--
Chris Winters
Creating enterprise-capable snack systems since 1988