I've come across this situation with Oracle. Here is how Class::DBI works in regards to has_a. 
__PACKAGE__->has_a(
    startdate => 'Date::Class',
    inflate => sub { Date::Class->new(shift) },
    deflate => 'some_method_name'
);

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In the above example, you tell Class::DBI that the field
startdate should be 'modeled' by a Date::Class object.
Thus when a record is retrieved from the database
the value stored in the database is passed to the
anonymous sub, the anonymous sub is expected to
return an object reference to a Date::Class object.
When you construct an object from scratch
(you are wanting to insert a new record).
A common misconception is that you put a string
representing the date when in fact you must instead
put an object reference to Date::Class. For example:

Incorrect:

SomeTab->create({startdate => '07/08/03'});

[download]

Correct:

SomeTab->create({startdate => Date::Class->new('07/08/03')});

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The deflate value if present is the name of a method of
the Date::Class object that will return a string of
the proper format for insertion into the database.
Or if Date::Class objects will stringify properly you
may leave the deflate key out all together.

We struggled with this for quite some time
only after reading through the Class::DBI code did I
come to this conclusion, as it is very poorly documented
One thing to note, you should replace Date::Class with
some real class which deals with dates.

For our purposes I used Date::EzDate, as it seemed to
easily support the most formats for parsing input
I subclassed Date::EzDate to get the default ouput
format that we needed to work.

I hope this helps if you need further assistance please
contact me, mgrubb-web-perlmonks at fifthvision dot net

In reply to Re: Date conversion with Class::DBI by linux454
in thread Date conversion with Class::DBI by bsb

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