org.apache.hadoop.hive.ql.optimizer.spark.SparkJoinHintOptimizer Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
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package org.apache.hadoop.hive.ql.optimizer.spark;
import java.util.Stack;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.lib.Node;
import org.apache.hadoop.hive.ql.lib.NodeProcessor;
import org.apache.hadoop.hive.ql.lib.NodeProcessorCtx;
import org.apache.hadoop.hive.ql.optimizer.BucketJoinProcCtx;
import org.apache.hadoop.hive.ql.optimizer.BucketMapjoinProc;
import org.apache.hadoop.hive.ql.optimizer.SortBucketJoinProcCtx;
import org.apache.hadoop.hive.ql.parse.ParseContext;
import org.apache.hadoop.hive.ql.parse.SemanticException;
import org.apache.hadoop.hive.ql.parse.spark.OptimizeSparkProcContext;
/**
* This processes joins in which user specified a hint to identify the small-table.
* Currently it takes a mapjoin already converted from hints, and converts it further
* to BucketMapJoin or SMBMapJoin using same small-table identification.
*
* The idea is eventually to process even hinted Mapjoin hints here,
* but due to code complexity in refactoring, that is still in Optimizer.
*/
public class SparkJoinHintOptimizer implements NodeProcessor {
private BucketMapjoinProc bucketMapJoinOptimizer;
private SparkSMBJoinHintOptimizer smbMapJoinOptimizer;
public SparkJoinHintOptimizer(ParseContext parseCtx) {
bucketMapJoinOptimizer = new BucketMapjoinProc(parseCtx);
smbMapJoinOptimizer = new SparkSMBJoinHintOptimizer(parseCtx);
}
@Override
public Object process(Node nd, Stack stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException {
OptimizeSparkProcContext context = (OptimizeSparkProcContext) procCtx;
HiveConf hiveConf = context.getParseContext().getConf();
// Convert from mapjoin to bucket map join if enabled.
if (hiveConf.getBoolVar(HiveConf.ConfVars.HIVEOPTBUCKETMAPJOIN)
|| hiveConf.getBoolVar(HiveConf.ConfVars.HIVEOPTSORTMERGEBUCKETMAPJOIN)) {
BucketJoinProcCtx bjProcCtx = new BucketJoinProcCtx(hiveConf);
bucketMapJoinOptimizer.process(nd, stack, bjProcCtx, nodeOutputs);
}
// Convert from bucket map join to sort merge bucket map join if enabled.
if (hiveConf.getBoolVar(HiveConf.ConfVars.HIVEOPTSORTMERGEBUCKETMAPJOIN)) {
SortBucketJoinProcCtx smbJoinCtx = new SortBucketJoinProcCtx(hiveConf);
smbMapJoinOptimizer.process(nd, stack, smbJoinCtx, nodeOutputs);
}
return null;
}
}