com.speedment.runtime.core.component.sql

Interface SqlStreamOptimizer<ENTITY>

Type Parameters:

ENTITY - Entity type

public interface SqlStreamOptimizer<ENTITY>

Author:

Per Minborg

Method Summary

Modifier and Type	Method and Description
<P extends Pipeline> Metrics	metrics(P initialPipeline, DbmsType dbmsType) Returns a metric of how well this optimizer can optimize the given pipeline.
<P extends Pipeline> P	optimize(P initialPipeline, SqlStreamOptimizerInfo<ENTITY> info, AsynchronousQueryResult<ENTITY> query) Returns an optimized pipeline, potentially by modifying the query.

Method Detail

metrics

<P extends Pipeline> Metrics metrics(P initialPipeline,
                                     DbmsType dbmsType)

Returns a metric of how well this optimizer can optimize the given pipeline. The best imaginable optimization metric is Integer.MAX_VALUE. If this optimizer cannot optimize the pipeline at all, then 0 should be returned.

As a rule of thumb, metrics could return the number of steps in the pipeline that it is able to eliminate times 10.

Type Parameters:

P - Pipeline type

Parameters:

initialPipeline - to optimize

dbmsType - the type of the database

Returns:

how well this optimizer can optimize the given pipeline

optimize

<P extends Pipeline> P optimize(P initialPipeline,
                                SqlStreamOptimizerInfo<ENTITY> info,
                                AsynchronousQueryResult<ENTITY> query)

Returns an optimized pipeline, potentially by modifying the query.

Type Parameters:

P - Pipeline type

Parameters:

initialPipeline - to use

info - about the SQL

query - to optimize

Returns:

an optimized pipeline