view release on metacpan or  search on metacpan

lib/Couchbase/Bucket.pm  view on Meta::CPAN

=head2 durability_batch($options)

I<Volatile - Subject to change>

Creates a new durability batch. A durability batch is a special kind of batch
where the contained commands can only be documents whose durability is to
be checked.

    my $batch;
    $batch = $cb->batch;
    $batch->upsert($_) for @docs;
    $batch->wait_all;

    $batch = $cb->durability_batch({ persist_to => 1, replicate_to => 2 });
    $batch->endure($_) for @docs;
    $batch->wait_all;


The C<options> passed can be C<persist_to> and C<replicate_to>. See the
L<"Durability Requirements"> section for information.


=head2 N1QL QUERIES (EXPERIMENTAL)


N1QL queries are available as an experimental feature of the client
library.

The N1QL API exposes two functions, both of which function
similarly to their view counterparts.

At the time of writing, the server does not include N1QL as an integrated
feature (because it is still experimental). This means it must be downloaded
as a standalone package
(see L<http://docs.couchbase.com/developer/n1ql-dp4/n1ql-intro.html>). Once
downloaded and configured, the C<_host> option should be passed to the
query function (as detailed below).

N1QL functions return a L<Couchbase::N1QL::Handle> object, which functions
similarly to L<Couchbase::View::Handle> (internally, they share a lot of
code).


=head3 query_slurp("query", $queryargs, $queryopts)

Issue an N1QL query. This will send the query to the server (encoding
any parameters as needed).

    my $rv = $cb->query_slurp(
        # Query string
        'SELECT *, META().id FROM travel WHERE travel.country = $country ',

        # Placeholder values
        { country => "Ecuador", },

        # Query options
        { _host => "localhost:8093" }
    );

    foreach my $row (@{$rv->rows}) {
        # do something with decoded JSON
    }


The C<queryargs> parameter can either be a hashref of named placeholders
(omiting of course, the leading C<$> which is handled internally), or it can
be an arrayref of positional placeholders (if your query uses positional
placeholders).

The C<queryopts> is a set of other modifiers for the query. Most of these
are sent to the server. One special parameter is the C<_host> parameter, which
points to a standalone instance of the N1QL Developer Preview installation;
a temporary necesity for pre-release versions. Using of the C<_host> paramter
will be removed once Couchbase Server is available (in release or pre-release)
with an integrated N1QL process.


=head3 query_iterator("query", $queryargs, $queryopts)

This function is to C<query_slurp> as C<view_iterator> is to C<view_slurp>.
In short, this allows an iterator over the rows, only fetching data from
the network as needed. This is more efficient (but a bit less simple to
use) than C<query_slurp>

    my $rv = $cb->query_iterator("select * from default");
    while ((my $row = $rv->next)) {
        # do something with row.
    }


=head2 VIEW (MAPREDUCE) QUERIES


View methods come in two flavors. One is an iterator which incrementally
fetches data from the network, while the other loads the entire data and
then returns. For small queries (i.e. those which do not return many
results), which API you use is a matter of personal preference. For larger
resultsets, however, it often becomes a necessity to not load the entire
dataset into RAM.

Both the C<view_slurp> and C<view_iterator> return L<Couchbase::View::Handle>
objects. This has been changed from previous versions which returned a
C<Couchbase::View::HandleInfo> object (Though the APIs remain the same).


=head3 view_slurp("design/view", %options)

Queries and returns the results of a view. The first argument may be provided
either as a string of C<"$design/$view"> or as a two-element array reference
containing the design and view respectively.

The C<%options> are options passed verbatim to the view engine. Some options
however are intercepted by the client, and modify how the view is queried.

=over

=item C<spatial>

Indicate that the queried view is a geospatial view. This is required since the
formatting of the internal URI is slightly different.