Re: search() without search criteria

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On Fri, Apr 29, 2005 at 09:19:32PM +0100, Will Hawes wrote:
> If anything, CDBI has an illogical approach to retrieving data because
> it uses three separate methods, search(), retrieve() and retrieve_all(),
> to do the job of SQL's SELECT statement.

One of the issues in ORM is the mismatch of ideas. This is one of them.
We don't have a select() method. This is deliberate.

> Ultimately "retrieve" and "retrieve_all" are just specific types of search. The former for a specific record in a table, the latter for all records. So these two statements would be the same:
> @cds = CD->retrieve_all({});
> @cds = CD->search({});

retrieve_all() shouldn't take restricting arguments. If you're doing
that then you're not retrieving all records.

search() shouldn't take no arguments, as then you're not doing a search.

> Using the latter method, a "search or browse" function can be made
> simpler. No need to modify your base class to have artificial columns
> and pass artificial stuff like "{1 => 1}" to search(). No need to test
> whether criteria were specified and if not, call to retrieve_all()
> instead. You just pass your user's search criteria directly to search()
> - if no criteria are specified, it just returns all records.

You don't need to have artifical columns and 1 => 1 searches to do that:

	sub My::CDBI::Subclass::search {
		my ($class, @args) = @_;
		return $class->retrieve_all unless @args;
		return $class->SUPER::search(@args);
	}

(Modifying this to cope with the case of no restrictions but with extra
options is left as a fairly simple exercise for the reader)

Tony