NAME

DBIx::CSSQuery - A Perl DBI extension module to let you fetch data with CSS query syntax.

VERSION

This document describes DBIx::CSSQuery version 0.03

SYNOPSIS

    use DBIx::CSSQuery;

    # setup
    db->attr(dbh => DBI->connect(...));


    # fetch all posts and do something with them
    db("posts")->each(sub {
        print $_[0]->{body};
    });

    # fetch one post as a hash
    my $post = db("posts[id=1]")->get(0);

DESCRIPTION

DBIx::CSSQuery is, currently, a proof of concept for what can be done with CSS query. For example, here's how you retrieve a collection of a collection of records from table "posts":

    db("posts")

The return value of such expression is an instance of DBIx::CSSQuery::Collection.

Here's how to iterate over thath collection:

    db("posts")->each(sub {
        my $item = shift;

        print $item->{body};
    });

It's also yet-another DBI abstraction layer of Perl module.

INTERFACE

db([ $selector ])

This method is exported to your namespace by default.

If selector is not given, it returns an DBIx::CSSQuery::DB object. It is required to set dbh attribute on this object before doing queries. Setting dbh is just thiS:

    db->attr( dbh => DBI->connect($dsn) );

Only after this is done, you may pass $selector into db, do some query:

    db("posts[id=1]")

At this moment, only very limited selector syntax is supported. Conceptually, tags are mapped to table names, attributes are mapped to table columns. So previous query is the same as this sql query:

    SELECT * FROM posts WHERE id = 1;

Except that it is not executing this sql statement right away, but wait until it is really required. Laziness is an important virtue in this module.

At this point, if the column type is string, it needs to be single-quoted, like posts[subject='hi']. If it's integer, it must not be quoted, like the example above. Hopefully this can be automatically detected on the backend so the selector syntax an be less strict.

This function returns an object of DBIx::CSSQuery::Collection, from which you will manipulate yout retrieved data set.

DEPENDENCIES

self, Sub::Exporter

INCOMPATIBILITIES

None reported.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-dbix-cssquery@rt.cpan.org, or through the web interface at http://rt.cpan.org.

AUTHOR

Kang-min Liu <gugod@gugod.org>

LICENCE AND COPYRIGHT

Copyright (c) 2008, Kang-min Liu <gugod@gugod.org>.

This software is released under the MIT license cited below.

The "MIT" License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

cpanm DBIx::CSSQuery

perl -MCPAN -e shell
install DBIx::CSSQuery