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
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.
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