Examples of IntroduceTwoStepAggregateRule

org.apache.vxquery.compiler.rewriter.rules.IntroduceTwoStepAggregateRule

The rule searches for aggregate operators with an aggregate function expression that has not been initialized for two step aggregation.

 Before plan__parent AGGREGATE( $v : af1( $v1 ) ) plan__child Where af1 is a VXquery aggregate function expression configured for single  step processing and $v1 is defined in plan__child. After if (af1 == count) aggregate operating settings: Step 1: count Step 2: sum if (af1 == avg) aggregate operating settings: Step 1: avg-local Step 2: avg-global if (af1 in (max, min, sum)) aggregate operating settings: Step 1: af1 Step 2: af1

@author prestonc


        // Find assign for scalar aggregate function.
        normalization.add(new ConvertAssignToAggregateRule());


        // Use two step aggregate operators if possible.
        normalization.add(new IntroduceTwoStepAggregateRule());


        // Used to clean up any missing noops after all the subplans have been altered.
        normalization.add(new RemoveRedundantVariablesRule());
        normalization.add(new RemoveUnusedAssignAndAggregateRule());


        // Find assign for scalar aggregate function.
        // normalization.add(new ConvertAssignToAggregateRule());


        // Use two step aggregate operators if possible.
        normalization.add(new IntroduceTwoStepAggregateRule());


        // Used to clean up any missing noops after all the subplans have been altered.
        normalization.add(new RemoveRedundantVariablesRule());
        normalization.add(new RemoveUnusedAssignAndAggregateRule());

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Examples of IntroduceTwoStepAggregateRule

Examples of org.apache.vxquery.compiler.rewriter.rules.IntroduceTwoStepAggregateRule

Examples of org.apache.vxquery.compiler.rewriter.rules.IntroduceTwoStepAggregateRule