com.bigdata.rdf.sparql.ast.optimizers
Class AskOptimizer

java.lang.Object
  com.bigdata.rdf.sparql.ast.optimizers.AskOptimizer

All Implemented Interfaces:

IASTOptimizer

public class AskOptimizer
extends Object
implements IASTOptimizer

ASK queries have a LIMIT of ONE imposed unless they are aggregations. TODO ASK style aggregations should always succeed (unless they encounter an error) and could be refactored into a subquery with a limit of ONE and an aggregation to ensure that they do the minimum possible work.

Constructor Summary

AskOptimizer()

Method Summary

IQueryNode

optimize(AST2BOpContext context, IQueryNode queryNode, IBindingSet[] bindingSet) Optimize the AST.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AskOptimizer

public AskOptimizer()

Method Detail

optimize

public IQueryNode optimize(AST2BOpContext context,
                           IQueryNode queryNode,
                           IBindingSet[] bindingSet)

Description copied from interface: IASTOptimizer

Optimize the AST.

Specified by:

optimize in interface IASTOptimizer

Parameters:

context - The evaluation context.

queryNode - The AST (in).

Returns:

The optimized AST.