Attean::AggregateExpression3pm

Version

This document describes Attean::AggregateExpression version 0.035

Overview

The Attean::AggregateExpression class represents an expression tree where the root node is an aggregate operation (e.g. SUM(?a) or COALESCE(?a/?b, ?c, 0)).

Roles

This role consumes the Attean::API::AggregateExpression role.

Attributes

The following attributes exist:

"operator"

The name of the aggregate operator, from the allowable set: COUNT, SUM, MIN, MAX, AVG, GROUP_CONCAT, SAMPLE.

"scalar_vars"

A HASH reference of scalar variables. The only scalar variable defined for SPARQL 1.1 is 'seperator', a string separator used with the GROUP_CONCAT aggregate.

"distinct"

A boolean indicating whether the aggregate should operate over distinct term sets, or full multisets.

"variable"

A Attean::API::Variable object which will be bound to the produced aggregate value in results.