NAME

RDF::Query::Algebra::Aggregate - Algebra class for aggregate patterns

VERSION

This document describes RDF::Query::Algebra::Aggregate version 2.201, released 30 January 2010.

METHODS

new ( $pattern, \@groupby, $alias = [$op => $col] )>

Returns a new Aggregate structure. Groups by the named bindings in @groupby, and returns new bindings for the named $alias for the operation $op on column $col.

$op may be one of: COUNT, MIN, MAX, SUM.

construct_args

Returns a list of arguments that, passed to this class' constructor, will produce a clone of this algebra pattern.

pattern

Returns the aggregates pattern.

groupby

Returns the aggregates GROUP BY binding names.

ops

Returns a list of tuples as ARRAY refs containing $alias, $op, $col.

sse

Returns the SSE string for this alegbra expression.

as_sparql

Returns the SPARQL string for this alegbra expression.

type

Returns the type of this algebra expression.

referenced_variables

Returns a list of the variable names used in this algebra expression.

binding_variables

Returns a list of the variable names used in this algebra expression that will bind values during execution.

definite_variables

Returns a list of the variable names that will be bound after evaluating this algebra expression.

fixup ( $query, $bridge, $base, \%namespaces )

Returns a new pattern that is ready for execution using the given bridge. This method replaces generic node objects with bridge-native objects.

execute ( $query, $bridge, \%bound, $context, %args )

AUTHOR

Gregory Todd Williams <gwilliams@cpan.org>