ANN: Lafcadio 0.8.0
Francis Hwang
contains more than 40 new features and bugfixes. And it adds lots of
convenience methods to DomainObject, richer query inference operators,
real-time query subset caching -- all in a slimmer codebase.
== What's Lafcadio? ==
Lafcadio is an object-relational mapping library for use with MySQL. It
supports a lot of advanced features, including extensive aid in mapping
to legacy databases, in-Ruby triggers, and an advanced query engine
that allows you to form queries in Ruby that can be run either against
the live database, or an in-memory mock store for testing purposes.
I use it in production code on a regular basis, most notably at
Rhizome.org, an online community with more than 1 million pageviews a
month.
http://lafcadio.rubyforge.org/
== What's new? ==
= Better operators for query inference:
class User < Lafcadio::DomainObject
strings :fname, :lname, :email
end
maybe_koreans = User.get { |u| u.lname.in( 'Park', 'Lee', 'Hwang' ) }
no_fname = User.get { |u| u.fname.nil? }
As always, these queries work both against MySQL and against a much
faster, in-memory mock object store for use in testing.
= Query Caching:
Everytime you run a select against the DB, Lafcadio caches the results
in memory. Then, if you later run a second select that is a subset of
the first, Lafcadio detects it, figures out what it's a subset of,
filters out the results in memory, and returns you the results. This
all happens transparently.
What does this mean? It means a significantly faster app, because if
you run these three queries:
select * from users where lname = 'Smith'
select * from users where lname = 'Smith' and fname like '%john%'
select * from users where lname = 'Smith' and email like '%hotmail%'
Lafcadio will only ask MySQL for the results for the first select
statement, and do the rest for you without using the DB connection.
= Convenience methods for DomainObject:
puts User.exist?
u = User[15]
u.update!( :fname => 'Bill' )
u.delete!
all_users = User.all
first_user = User.first
last_user = User.last