Do Moose and DBIx::Class go together like bread and butter? I'm currently using Moose and DBIx::Simple but I have a sneaking feeling that DBIx::Class would be sheer nirvana in this situation.

OK, so I have a bunch of classes which all inherit a base class method to obtain new data: 

sub getnew {
    my ($self) = @_;

    $self->dbs->query($self->getnewsql)->hashes;
}

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Now, getnewsql is a lazy-built method. In the first level of derived classes, the following role is used by some classes to get new data: 
package Local::GetDataTable;

use Moose::Role;

sub _build_getnewsql {
  my ($self)=@_;

  sprintf "SELECT * FROM %s WHERE qblistid IS NULL and qbresponse IS N
+ULL",
    $self->dbtable;

};

1;

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Now, in a class which needs to refine the WHERE clause with another clause, we override this lazy builder as follows: 
override '_build_getnewsql' => sub {
    my ($self) = @_;
    my $sql = super();
    $sql .= sprintf "AND location = %d", $self->location;
};

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eewww, it's so stringy

I wonder if there is some way to do this with methods? DBIx::Class uses data structures to build SQL via SQL::Abstract and so the lack of methods there makes me wonder if there is a way to extend the query data structures in an OO-fashion

make a view my friend?

ORMesque has a different take on object-relational Perl - simply build database views for each thing you need. Why am I doing all this dynamic query extension in OO Perl anyway? An alterative approach would be to simply map my various program query requirements to database views.

I think it's interesting to explore how best to tread the line between programming languages and relational database engines. I suppose that using an ORM allows you to be more dynamic but I'm not sure.

recent threads

a recent thread shows resultset restriction but not extension. I'd be curious as to how to extend things with DBIx::Class... or your opinion on database views as an alternative approach.

living breathing code

I wrote DBIx::Cookbook to build up an executable comparison reference, so contributions there are welcome too.



The mantra of every experienced web application developer is the same: thou shalt separate business logic from display. Ironically, almost all template engines allow violation of this separation principle, which is the very impetus for HTML template engine development.

-- Terence Parr, "Enforcing Strict Model View Separation in Template Engines"

In reply to DBIx::Class, make me drool by metaperl

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