How do you do it?

I've build my own persistent objects solution for a client that had some very strict rules on their system that made most CPAN modules unusable.

In this system I have one or more engines that correspond to a DBI connection, and other objects that correspond to rows in a table (one table per class).

You can fetch specific objects from the engine by giving it the classname and id (or constraints that correspond to WHERE queries):

my $object = $engine->get('Some::Object',$object_id);
my @objects = $engine->mget($class,{ name => value, name2 =>  value2 }
+);
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Saving is done by explicitly calling the save() method:

my $value = $object->get('name');
$object->set('name','other value');
$object->save();
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And objects are passed their engine at creation, so they know where to save their data:

my $object = Object->new($engine,%attributes);
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This system doesn't try to be transparant, which has two advantages:

• The programmer knows when updates/insert statements are sent to the database: when the save() method is called. (or he can choose to destroy the object without saving)
• The programmer can do searches on key => value pairs or WHERE queries, which turns out to be very useful (after all, when you've got a database, you'd better make use of the features it has too).

I've recently tried Class::DBI and it seems to do it pretty much the same, except that the DBI connection is global for a given class, which I don't like one bit.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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