NAME¶
Alzabo::Runtime::JoinCursor - Cursor that returns arrays of
"Alzabo::Runtime::Row" objects
SYNOPSIS¶
use Alzabo::Runtime::JoinCursor;
my $cursor = $schema->join( tables => [ $foo, $bar ],
where => [ $foo->column('foo_id'), '=', 1 ] );
while ( my @rows = $cursor->next )
{
print $rows[0]->select('foo'), "\n";
print $rows[1]->select('bar'), "\n";
}
DESCRIPTION¶
Objects in this class are used to return arrays of Alzabo::Runtime::Row objects
when requested. The cursor does not preload objects but rather creates them on
demand, which is much more efficient. For more details on the rational please
see the RATIONALE FOR CURSORS section in Alzabo::Design.
INHERITS FROM¶
"Alzabo::Runtime::Cursor"
METHODS¶
next¶
Returns the next array of "Alzabo::Runtime::Row" objects or an empty
list if no more are available.
If an individual row could not be fetched, then the array may contain some
"undef" values. For outer joins, this is normal behavior, but for
regular joins, this probably indicates a data error.
all_rows¶
This method fetches all the rows available from the current point onwards. This
means that if there are five set of rows that will be returned when the object
is created and you call "next()" twice, calling
"all_rows()" after it will only return three sets.
The return value is an array of array references. Each of these references
represents a single set of rows as they would be returned from the
"next" method.
reset¶
Resets the cursor so that the next "next()" call will return the first
row of the set.
count¶
Returns the number of rowsets returned by the cursor so far.
next_as_hash¶
Returns the next rows in a hash, where the hash keys are the table names and the
hash values are the row object. If a table has been included in the join via
an outer join, then it is only included in the hash if there is a row for that
table.
AUTHOR¶
Dave Rolsky, <autarch@urth.org>