NestedLoopJoinNode.java
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// to you under the Apache License, Version 2.0 (the
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package org.apache.doris.planner;
import org.apache.doris.analysis.Expr;
import org.apache.doris.analysis.ExprSubstitutionMap;
import org.apache.doris.analysis.JoinOperator;
import org.apache.doris.analysis.SlotId;
import org.apache.doris.analysis.TupleDescriptor;
import org.apache.doris.analysis.TupleId;
import org.apache.doris.statistics.StatisticalType;
import org.apache.doris.thrift.TExplainLevel;
import org.apache.doris.thrift.TNestedLoopJoinNode;
import org.apache.doris.thrift.TPlanNode;
import org.apache.doris.thrift.TPlanNodeType;
import com.google.common.base.MoreObjects;
import com.google.common.collect.Lists;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import java.util.Collections;
import java.util.List;
/**
* Nested loop join between left child and right child.
*/
public class NestedLoopJoinNode extends JoinNodeBase {
private static final Logger LOG = LogManager.getLogger(NestedLoopJoinNode.class);
// If isOutputLeftSideOnly=true, the data from the left table is returned directly without a join operation.
// This is used to optimize `in bitmap`, because bitmap will make a lot of copies when doing Nested Loop Join,
// which is very resource intensive.
// `in bitmap` has two cases:
// 1. select * from tbl1 where k1 in (select bitmap_col from tbl2);
// This will generate a bitmap runtime filter to filter the left table, because the bitmap is an exact filter
// and does not need to be filtered again in the NestedLoopJoinNode, so it returns the left table data directly.
// 2. select * from tbl1 where 1 in (select bitmap_col from tbl2);
// This sql will be rewritten to
// "select * from tbl1 left semi join tbl2 where bitmap_contains(tbl2.bitmap_col, 1);"
// return all data in the left table to parent node when there is data on the build side, and return empty when
// there is no data on the build side.
private boolean isOutputLeftSideOnly = false;
private List<Expr> runtimeFilterExpr = Lists.newArrayList();
private List<Expr> joinConjuncts;
private List<Expr> markJoinConjuncts;
public static boolean canParallelize(JoinOperator joinOp) {
return joinOp == JoinOperator.CROSS_JOIN || joinOp == JoinOperator.INNER_JOIN
|| joinOp == JoinOperator.LEFT_OUTER_JOIN || joinOp == JoinOperator.LEFT_SEMI_JOIN
|| joinOp == JoinOperator.LEFT_ANTI_JOIN || joinOp == JoinOperator.NULL_AWARE_LEFT_ANTI_JOIN;
}
public void setJoinConjuncts(List<Expr> joinConjuncts) {
this.joinConjuncts = joinConjuncts;
}
public void setMarkJoinConjuncts(List<Expr> markJoinConjuncts) {
this.markJoinConjuncts = markJoinConjuncts;
}
/**
* Only for Nereids.
*/
public NestedLoopJoinNode(PlanNodeId id, PlanNode outer, PlanNode inner, List<TupleId> tupleIds,
JoinOperator joinOperator, List<Expr> srcToOutputList, TupleDescriptor intermediateTuple,
TupleDescriptor outputTuple, boolean isMarkJoin) {
super(id, "NESTED LOOP JOIN", StatisticalType.NESTED_LOOP_JOIN_NODE, joinOperator, isMarkJoin);
this.tupleIds.addAll(tupleIds);
children.add(outer);
children.add(inner);
// TODO: need to set joinOp by Nereids
// Inherits all the nullable tuple from the children
// Mark tuples that form the "nullable" side of the outer join as nullable.
nullableTupleIds.addAll(outer.getNullableTupleIds());
nullableTupleIds.addAll(inner.getNullableTupleIds());
if (joinOp.equals(JoinOperator.FULL_OUTER_JOIN)) {
nullableTupleIds.addAll(outer.getTupleIds());
nullableTupleIds.addAll(inner.getTupleIds());
} else if (joinOp.equals(JoinOperator.LEFT_OUTER_JOIN)) {
nullableTupleIds.addAll(inner.getTupleIds());
} else if (joinOp.equals(JoinOperator.RIGHT_OUTER_JOIN)) {
nullableTupleIds.addAll(outer.getTupleIds());
}
vIntermediateTupleDescList = Lists.newArrayList(intermediateTuple);
outputTupleDesc = outputTuple;
vSrcToOutputSMap = new ExprSubstitutionMap(srcToOutputList, Collections.emptyList());
}
public void setOutputLeftSideOnly(boolean outputLeftSideOnly) {
isOutputLeftSideOnly = outputLeftSideOnly;
}
public List<Expr> getRuntimeFilterExpr() {
return runtimeFilterExpr;
}
@Override
protected String debugString() {
return MoreObjects.toStringHelper(this).addValue(super.debugString()).toString();
}
@Override
protected void toThrift(TPlanNode msg) {
msg.nested_loop_join_node = new TNestedLoopJoinNode();
msg.nested_loop_join_node.join_op = joinOp.toThrift();
for (Expr conjunct : joinConjuncts) {
msg.nested_loop_join_node.addToJoinConjuncts(conjunct.treeToThrift());
}
if (markJoinConjuncts != null) {
for (Expr conjunct : markJoinConjuncts) {
msg.nested_loop_join_node.addToMarkJoinConjuncts(conjunct.treeToThrift());
}
}
msg.nested_loop_join_node.setIsMark(isMarkJoin());
if (vIntermediateTupleDescList != null) {
for (TupleDescriptor tupleDescriptor : vIntermediateTupleDescList) {
msg.nested_loop_join_node.addToVintermediateTupleIdList(tupleDescriptor.getId().asInt());
}
}
msg.nested_loop_join_node.setIsOutputLeftSideOnly(isOutputLeftSideOnly);
msg.nested_loop_join_node.setUseSpecificProjections(false);
msg.node_type = TPlanNodeType.CROSS_JOIN_NODE;
}
@Override
public String getNodeExplainString(String detailPrefix, TExplainLevel detailLevel) {
String distrModeStr = "";
StringBuilder output =
new StringBuilder().append(detailPrefix).append("join op: ").append(joinOp.toString()).append("(")
.append(distrModeStr).append(")\n");
if (detailLevel == TExplainLevel.BRIEF) {
output.append(detailPrefix).append(
String.format("cardinality=%,d", cardinality)).append("\n");
return output.toString();
}
if (!joinConjuncts.isEmpty()) {
output.append(detailPrefix).append("join conjuncts: ").append(getExplainString(joinConjuncts)).append("\n");
}
if (markJoinConjuncts != null && !markJoinConjuncts.isEmpty()) {
output.append(detailPrefix).append("mark join predicates: ")
.append(getExplainString(markJoinConjuncts)).append("\n");
}
if (!conjuncts.isEmpty()) {
output.append(detailPrefix).append("predicates: ").append(getExplainString(conjuncts)).append("\n");
}
output.append(detailPrefix).append("is output left side only: ").append(isOutputLeftSideOnly).append("\n");
output.append(detailPrefix).append(String.format("cardinality=%,d", cardinality)).append("\n");
if (vIntermediateTupleDescList != null) {
output.append(detailPrefix).append("vIntermediate tuple ids: ");
for (TupleDescriptor tupleDescriptor : vIntermediateTupleDescList) {
output.append(tupleDescriptor.getId()).append(" ");
}
output.append("\n");
}
if (outputSlotIds != null) {
output.append(detailPrefix).append("output slot ids: ");
for (SlotId slotId : outputSlotIds) {
output.append(slotId).append(" ");
}
output.append("\n");
}
if (detailLevel == TExplainLevel.VERBOSE) {
output.append(detailPrefix).append("isMarkJoin: ").append(isMarkJoin()).append("\n");
}
return output.toString();
}
/**
* If joinOp is one of type below:
* 1. RIGHT_OUTER_JOIN
* 2. RIGHT_ANTI_JOIN
* 3. RIGHT_SEMI_JOIN
* 4. FULL_OUTER_JOIN
*
* Probe-side must have full data so join is a serial operator.
*/
@Override
public boolean isSerialOperator() {
return joinOp == JoinOperator.RIGHT_OUTER_JOIN || joinOp == JoinOperator.RIGHT_ANTI_JOIN
|| joinOp == JoinOperator.RIGHT_SEMI_JOIN || joinOp == JoinOperator.FULL_OUTER_JOIN;
}
}