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

This document describes RDF::Query::Algebra::Aggregate version 2.907.

Beyond the methods documented below, this class inherits methods from the RDF::Query::Algebra class.

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

new ( $pattern, \@groupby, expressions = [ $alias => [$op, \%options, @cols] ] )>

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 aggregate's GROUP BY binding names.

ops

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

sse

Returns the SSE string for this algebra expression.

as_sparql

Returns the SPARQL string for this algebra expression.

as_hash

Returns the query as a nested set of plain data structures (no objects).

type

Returns the type of this algebra expression.

referenced_variables

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

potentially_bound

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.

 Gregory Todd Williams <gwilliams@cpan.org>