mihaibudiu commented on code in PR #4267:
URL: https://github.com/apache/calcite/pull/4267#discussion_r2038024381


##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns

Review Comment:
   The first phrase is good, but the second does not really have anything to do 
with the description of this parameter



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates

Review Comment:
   You return a single node, so it must be a single predicate, which perhaps 
has a specific form.



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates
+   */
+  private RexNode apply(
+      RexNode condition,
+      RelNode relNode,
+      List<RelDataTypeField> fieldList,
+      RelBuilder relBuilder,
+      RelMetadataQuery mq) {
+    final Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef = new 
HashMap<>();
+
+    ImmutableBitSet columnBits = RelOptUtil.InputFinder.bits(condition);
+    if (columnBits.isEmpty()) {
+      return condition;
+    }
+
+    // Trace which table does the column referenced in the condition come from
+    for (int columnBit : columnBits.asList()) {
+      Set<RexNode> exprLineage =
+          mq.getExpressionLineage(
+              relNode,
+              RexInputRef.of(columnBit, fieldList));
+      // If mq.getExpressionLineage cannot get result, skip it
+      if (exprLineage == null) {
+        continue;
+      }
+      Set<RexTableInputRef.RelTableRef> relTableRefs =
+          RexUtil.gatherTableReferences(Lists.newArrayList(exprLineage));
+      // If the column comes from multiple tables, skip it
+      if (relTableRefs.isEmpty() || relTableRefs.size() > 1) {
+        continue;
+      }
+      inputRefToTableRef.put(columnBit, relTableRefs.iterator().next());
+    }
+
+    ExpandDisjunctionForTableHelper expandHelper =
+        new ExpandDisjunctionForTableHelper(inputRefToTableRef, relBuilder, 
config.bloat());
+    Map<RexTableInputRef.RelTableRef, RexNode> expandResult = 
expandHelper.expand(condition);
+
+    RexNode newCondition = condition;
+    for (RexNode expandCondition : expandResult.values()) {
+      newCondition = relBuilder.and(newCondition, expandCondition);
+    }
+    return newCondition;
+  }
+
+  private static void matchFilter(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Filter filter = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    RexNode newCondition =
+        rule.apply(
+            filter.getCondition(),
+            filter,
+            filter.getRowType().getFieldList(),
+            relBuilder,
+            mq);
+    if (newCondition.equals(filter.getCondition())) {
+      return;
+    }
+    Filter newFilter = filter.copy(filter.getTraitSet(), filter.getInput(), 
newCondition);
+    call.transformTo(newFilter);
+  }
+
+  private static void matchJoin(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Join join = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    List<RelDataTypeField> fieldList =
+        Lists.newArrayList(join.getLeft().getRowType().getFieldList());
+    fieldList.addAll(join.getRight().getRowType().getFieldList());
+    RexNode newCondition =
+        rule.apply(
+            join.getCondition(),
+            join,
+            fieldList,
+            relBuilder,
+            mq);
+    if (newCondition.equals(join.getCondition())) {
+      return;
+    }
+    Join newJoin =
+        join.copy(
+            join.getTraitSet(),
+            newCondition,
+            join.getLeft(),
+            join.getRight(),
+            join.getJoinType(),
+            join.isSemiJoinDone());
+    call.transformTo(newJoin);
+  }
+
+  /**
+   * Helper class to expand predicates.
+   */
+  private static class ExpandDisjunctionForTableHelper {
+
+    private final Map<Integer, RexTableInputRef.RelTableRef> 
inputRefToTableRef;
+
+    private final RelBuilder relBuilder;
+
+    private final int maxNodeCount;
+
+    // Used to record the number of redundant expressions expanded.
+    private int currentCount;
+
+    private ExpandDisjunctionForTableHelper(
+        Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef,
+        RelBuilder relBuilder,
+        int maxNodeCount) {
+      this.inputRefToTableRef = inputRefToTableRef;
+      this.relBuilder = relBuilder;
+      this.maxNodeCount = maxNodeCount;
+    }
+
+    private Map<RexTableInputRef.RelTableRef, RexNode> expand(RexNode 
condition) {
+      try {
+        this.currentCount = 0;
+        return expandDeep(condition);
+      } catch (OverLimitException e) {
+        return new HashMap<>();
+      }
+    }
+
+    /**
+     * Expand predicates recursively that can be pushed down to single table.
+     *
+     * @param condition   Predicate to be expanded
+     * @return  Additional predicates that can be pushed down for each table
+     */
+    private Map<RexTableInputRef.RelTableRef, RexNode> expandDeep(RexNode 
condition) {
+      Map<RexTableInputRef.RelTableRef, RexNode> additionalConditions = new 
HashMap<>();
+
+      ImmutableBitSet inputRefs = RelOptUtil.InputFinder.bits(condition);
+      if (inputRefs.isEmpty()) {
+        return additionalConditions;
+      }
+
+      RexTableInputRef.RelTableRef tableRef = 
inputRefsBelongToOneTable(inputRefs);
+      // The condition already belongs to one table, return it directly
+      if (tableRef != null) {
+        checkExpandCount(condition.nodeCount());
+        additionalConditions.put(tableRef, condition);
+        return additionalConditions;
+      }
+
+      // Recursively expand the expression according to whether it is a 
conjunction
+      // or a disjunction. If it is neither a disjunction nor a conjunction, 
it cannot
+      // be expanded further and an empty Map is returned.
+      switch (condition.getKind()) {
+      case AND:
+        List<RexNode> andOperands = RexUtil.flattenAnd(((RexCall) 
condition).getOperands());
+        for (RexNode andOperand : andOperands) {
+          Map<RexTableInputRef.RelTableRef, RexNode> operandResult = 
expandDeep(andOperand);
+          mergeAnd(additionalConditions, operandResult);
+        }
+        break;
+      case OR:
+        List<RexNode> orOperands = RexUtil.flattenOr(((RexCall) 
condition).getOperands());
+        additionalConditions.putAll(expandDeep(orOperands.get(0)));
+        for (int i = 1; i < orOperands.size(); i++) {
+          Map<RexTableInputRef.RelTableRef, RexNode> operandResult =
+              expandDeep(orOperands.get(i));
+          mergeOr(additionalConditions, operandResult);
+
+          if (additionalConditions.isEmpty()) {
+            break;
+          }
+        }
+        break;
+      default:
+        break;
+      }
+
+      return additionalConditions;
+    }
+
+    private RexTableInputRef.@Nullable RelTableRef inputRefsBelongToOneTable(
+        ImmutableBitSet inputRefs) {
+      RexTableInputRef.RelTableRef tableRef = 
inputRefToTableRef.get(inputRefs.nth(0));
+      if (tableRef == null) {
+        return null;
+      }
+      for (int inputBit : inputRefs.asList()) {
+        RexTableInputRef.RelTableRef inputBitTableRef = 
inputRefToTableRef.get(inputBit);
+        if (!tableRef.equals(inputBitTableRef)) {
+          return null;
+        }
+      }
+      return tableRef;
+    }
+
+    /**
+     * For additional predicates of each operand in conjunction, all of them 
should be retained and

Review Comment:
   combine predicates that depend on the same table using conjunctions
   specify that the result is returned by modifying baseMap
   (you could also rename the function to combinePredicatesUsingAnd)



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates
+   */
+  private RexNode apply(
+      RexNode condition,
+      RelNode relNode,
+      List<RelDataTypeField> fieldList,
+      RelBuilder relBuilder,
+      RelMetadataQuery mq) {
+    final Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef = new 
HashMap<>();
+
+    ImmutableBitSet columnBits = RelOptUtil.InputFinder.bits(condition);
+    if (columnBits.isEmpty()) {
+      return condition;
+    }
+
+    // Trace which table does the column referenced in the condition come from
+    for (int columnBit : columnBits.asList()) {
+      Set<RexNode> exprLineage =
+          mq.getExpressionLineage(
+              relNode,
+              RexInputRef.of(columnBit, fieldList));
+      // If mq.getExpressionLineage cannot get result, skip it
+      if (exprLineage == null) {
+        continue;
+      }
+      Set<RexTableInputRef.RelTableRef> relTableRefs =
+          RexUtil.gatherTableReferences(Lists.newArrayList(exprLineage));
+      // If the column comes from multiple tables, skip it
+      if (relTableRefs.isEmpty() || relTableRefs.size() > 1) {
+        continue;
+      }
+      inputRefToTableRef.put(columnBit, relTableRefs.iterator().next());
+    }
+
+    ExpandDisjunctionForTableHelper expandHelper =
+        new ExpandDisjunctionForTableHelper(inputRefToTableRef, relBuilder, 
config.bloat());
+    Map<RexTableInputRef.RelTableRef, RexNode> expandResult = 
expandHelper.expand(condition);
+
+    RexNode newCondition = condition;
+    for (RexNode expandCondition : expandResult.values()) {
+      newCondition = relBuilder.and(newCondition, expandCondition);
+    }
+    return newCondition;
+  }
+
+  private static void matchFilter(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Filter filter = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    RexNode newCondition =
+        rule.apply(
+            filter.getCondition(),
+            filter,
+            filter.getRowType().getFieldList(),
+            relBuilder,
+            mq);
+    if (newCondition.equals(filter.getCondition())) {
+      return;
+    }
+    Filter newFilter = filter.copy(filter.getTraitSet(), filter.getInput(), 
newCondition);
+    call.transformTo(newFilter);
+  }
+
+  private static void matchJoin(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Join join = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    List<RelDataTypeField> fieldList =
+        Lists.newArrayList(join.getLeft().getRowType().getFieldList());
+    fieldList.addAll(join.getRight().getRowType().getFieldList());
+    RexNode newCondition =
+        rule.apply(
+            join.getCondition(),
+            join,
+            fieldList,
+            relBuilder,
+            mq);
+    if (newCondition.equals(join.getCondition())) {
+      return;
+    }
+    Join newJoin =
+        join.copy(
+            join.getTraitSet(),
+            newCondition,
+            join.getLeft(),
+            join.getRight(),
+            join.getJoinType(),
+            join.isSemiJoinDone());
+    call.transformTo(newJoin);
+  }
+
+  /**
+   * Helper class to expand predicates.
+   */
+  private static class ExpandDisjunctionForTableHelper {
+
+    private final Map<Integer, RexTableInputRef.RelTableRef> 
inputRefToTableRef;
+
+    private final RelBuilder relBuilder;
+
+    private final int maxNodeCount;
+
+    // Used to record the number of redundant expressions expanded.
+    private int currentCount;
+
+    private ExpandDisjunctionForTableHelper(
+        Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef,
+        RelBuilder relBuilder,
+        int maxNodeCount) {
+      this.inputRefToTableRef = inputRefToTableRef;
+      this.relBuilder = relBuilder;
+      this.maxNodeCount = maxNodeCount;
+    }
+
+    private Map<RexTableInputRef.RelTableRef, RexNode> expand(RexNode 
condition) {
+      try {
+        this.currentCount = 0;
+        return expandDeep(condition);
+      } catch (OverLimitException e) {
+        return new HashMap<>();
+      }
+    }
+
+    /**
+     * Expand predicates recursively that can be pushed down to single table.
+     *
+     * @param condition   Predicate to be expanded
+     * @return  Additional predicates that can be pushed down for each table
+     */
+    private Map<RexTableInputRef.RelTableRef, RexNode> expandDeep(RexNode 
condition) {
+      Map<RexTableInputRef.RelTableRef, RexNode> additionalConditions = new 
HashMap<>();
+
+      ImmutableBitSet inputRefs = RelOptUtil.InputFinder.bits(condition);
+      if (inputRefs.isEmpty()) {
+        return additionalConditions;
+      }
+
+      RexTableInputRef.RelTableRef tableRef = 
inputRefsBelongToOneTable(inputRefs);
+      // The condition already belongs to one table, return it directly

Review Comment:
   this comment should be after the if



##########
core/src/main/java/org/apache/calcite/rel/rules/CoreRules.java:
##########
@@ -853,13 +853,13 @@ private CoreRules() {}
 
   /** Rule that expand disjuction in condition of a {@link Filter}.
    *
-   * @see #EXPAND_JOIN_DISJUCTION */
-  public static final ExpandDisjuctionRule EXPAND_FILTER_DISJUCTION =
-      ExpandDisjuctionRule.Config.FILTER.toRule();
+   * @see #EXPAND_JOIN_DISJUNCTION_FOR_TABLE */

Review Comment:
   I see what FOR_TABLE means, but I am not sure it's the best name.
   How about EXPAND_JOIN_DISJUNCTION_GLOBAL?
   



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates
+   */
+  private RexNode apply(
+      RexNode condition,
+      RelNode relNode,
+      List<RelDataTypeField> fieldList,
+      RelBuilder relBuilder,
+      RelMetadataQuery mq) {
+    final Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef = new 
HashMap<>();
+
+    ImmutableBitSet columnBits = RelOptUtil.InputFinder.bits(condition);
+    if (columnBits.isEmpty()) {
+      return condition;
+    }
+
+    // Trace which table does the column referenced in the condition come from
+    for (int columnBit : columnBits.asList()) {
+      Set<RexNode> exprLineage =
+          mq.getExpressionLineage(
+              relNode,
+              RexInputRef.of(columnBit, fieldList));
+      // If mq.getExpressionLineage cannot get result, skip it
+      if (exprLineage == null) {
+        continue;
+      }
+      Set<RexTableInputRef.RelTableRef> relTableRefs =
+          RexUtil.gatherTableReferences(Lists.newArrayList(exprLineage));
+      // If the column comes from multiple tables, skip it
+      if (relTableRefs.isEmpty() || relTableRefs.size() > 1) {
+        continue;
+      }
+      inputRefToTableRef.put(columnBit, relTableRefs.iterator().next());
+    }
+
+    ExpandDisjunctionForTableHelper expandHelper =
+        new ExpandDisjunctionForTableHelper(inputRefToTableRef, relBuilder, 
config.bloat());
+    Map<RexTableInputRef.RelTableRef, RexNode> expandResult = 
expandHelper.expand(condition);
+
+    RexNode newCondition = condition;
+    for (RexNode expandCondition : expandResult.values()) {
+      newCondition = relBuilder.and(newCondition, expandCondition);
+    }
+    return newCondition;
+  }
+
+  private static void matchFilter(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Filter filter = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    RexNode newCondition =
+        rule.apply(
+            filter.getCondition(),
+            filter,
+            filter.getRowType().getFieldList(),
+            relBuilder,
+            mq);
+    if (newCondition.equals(filter.getCondition())) {
+      return;
+    }
+    Filter newFilter = filter.copy(filter.getTraitSet(), filter.getInput(), 
newCondition);
+    call.transformTo(newFilter);
+  }
+
+  private static void matchJoin(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Join join = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    List<RelDataTypeField> fieldList =
+        Lists.newArrayList(join.getLeft().getRowType().getFieldList());
+    fieldList.addAll(join.getRight().getRowType().getFieldList());
+    RexNode newCondition =
+        rule.apply(
+            join.getCondition(),
+            join,
+            fieldList,
+            relBuilder,
+            mq);
+    if (newCondition.equals(join.getCondition())) {
+      return;
+    }
+    Join newJoin =
+        join.copy(
+            join.getTraitSet(),
+            newCondition,
+            join.getLeft(),
+            join.getRight(),
+            join.getJoinType(),
+            join.isSemiJoinDone());
+    call.transformTo(newJoin);
+  }
+
+  /**
+   * Helper class to expand predicates.
+   */
+  private static class ExpandDisjunctionForTableHelper {
+
+    private final Map<Integer, RexTableInputRef.RelTableRef> 
inputRefToTableRef;
+
+    private final RelBuilder relBuilder;
+
+    private final int maxNodeCount;
+
+    // Used to record the number of redundant expressions expanded.
+    private int currentCount;
+
+    private ExpandDisjunctionForTableHelper(
+        Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef,
+        RelBuilder relBuilder,
+        int maxNodeCount) {
+      this.inputRefToTableRef = inputRefToTableRef;
+      this.relBuilder = relBuilder;
+      this.maxNodeCount = maxNodeCount;
+    }
+
+    private Map<RexTableInputRef.RelTableRef, RexNode> expand(RexNode 
condition) {
+      try {
+        this.currentCount = 0;
+        return expandDeep(condition);
+      } catch (OverLimitException e) {
+        return new HashMap<>();
+      }
+    }
+
+    /**
+     * Expand predicates recursively that can be pushed down to single table.
+     *
+     * @param condition   Predicate to be expanded
+     * @return  Additional predicates that can be pushed down for each table

Review Comment:
   a map from a table to a (combined) predicate that can be pushed down and 
only depends on columns of the table



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates
+   */
+  private RexNode apply(
+      RexNode condition,
+      RelNode relNode,
+      List<RelDataTypeField> fieldList,
+      RelBuilder relBuilder,
+      RelMetadataQuery mq) {
+    final Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef = new 
HashMap<>();
+
+    ImmutableBitSet columnBits = RelOptUtil.InputFinder.bits(condition);
+    if (columnBits.isEmpty()) {
+      return condition;
+    }
+
+    // Trace which table does the column referenced in the condition come from
+    for (int columnBit : columnBits.asList()) {
+      Set<RexNode> exprLineage =
+          mq.getExpressionLineage(
+              relNode,
+              RexInputRef.of(columnBit, fieldList));
+      // If mq.getExpressionLineage cannot get result, skip it
+      if (exprLineage == null) {
+        continue;
+      }
+      Set<RexTableInputRef.RelTableRef> relTableRefs =
+          RexUtil.gatherTableReferences(Lists.newArrayList(exprLineage));
+      // If the column comes from multiple tables, skip it
+      if (relTableRefs.isEmpty() || relTableRefs.size() > 1) {
+        continue;
+      }
+      inputRefToTableRef.put(columnBit, relTableRefs.iterator().next());
+    }
+
+    ExpandDisjunctionForTableHelper expandHelper =
+        new ExpandDisjunctionForTableHelper(inputRefToTableRef, relBuilder, 
config.bloat());
+    Map<RexTableInputRef.RelTableRef, RexNode> expandResult = 
expandHelper.expand(condition);
+
+    RexNode newCondition = condition;
+    for (RexNode expandCondition : expandResult.values()) {
+      newCondition = relBuilder.and(newCondition, expandCondition);
+    }
+    return newCondition;
+  }
+
+  private static void matchFilter(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Filter filter = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    RexNode newCondition =
+        rule.apply(
+            filter.getCondition(),
+            filter,
+            filter.getRowType().getFieldList(),
+            relBuilder,
+            mq);
+    if (newCondition.equals(filter.getCondition())) {
+      return;
+    }
+    Filter newFilter = filter.copy(filter.getTraitSet(), filter.getInput(), 
newCondition);
+    call.transformTo(newFilter);
+  }
+
+  private static void matchJoin(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Join join = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    List<RelDataTypeField> fieldList =
+        Lists.newArrayList(join.getLeft().getRowType().getFieldList());
+    fieldList.addAll(join.getRight().getRowType().getFieldList());
+    RexNode newCondition =
+        rule.apply(
+            join.getCondition(),
+            join,
+            fieldList,
+            relBuilder,
+            mq);
+    if (newCondition.equals(join.getCondition())) {
+      return;
+    }
+    Join newJoin =
+        join.copy(
+            join.getTraitSet(),
+            newCondition,
+            join.getLeft(),
+            join.getRight(),
+            join.getJoinType(),
+            join.isSemiJoinDone());
+    call.transformTo(newJoin);
+  }
+
+  /**
+   * Helper class to expand predicates.
+   */
+  private static class ExpandDisjunctionForTableHelper {
+

Review Comment:
   no need for so many empty lines here



##########
core/src/main/java/org/apache/calcite/rel/rules/ExpandDisjunctionForTableRule.java:
##########
@@ -0,0 +1,430 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.rel.rules;
+
+import org.apache.calcite.plan.RelOptRuleCall;
+import org.apache.calcite.plan.RelOptUtil;
+import org.apache.calcite.plan.RelRule;
+import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.Filter;
+import org.apache.calcite.rel.core.Join;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
+import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexCall;
+import org.apache.calcite.rex.RexInputRef;
+import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexTableInputRef;
+import org.apache.calcite.rex.RexUtil;
+import org.apache.calcite.tools.RelBuilder;
+import org.apache.calcite.util.ControlFlowException;
+import org.apache.calcite.util.ImmutableBitSet;
+
+import com.google.common.collect.Lists;
+
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Rule to expand disjunction for single table in condition of a {@link 
Filter} or {@link Join},
+ * It makes sense to make this optimization part of the predicate pushdown. 
For example:
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * }</pre></blockquote>
+ *
+ * <p>we can expand to obtain the condition
+ *
+ * <blockquote><pre>{@code
+ * select t1.name from t1, t2
+ * where t1.id = t2.id
+ * and (
+ *  (t1.id > 20 and t2.height < 50)
+ *  or
+ *  (t1.weight < 200 and t2.sales > 100)
+ * )
+ * and (t1.id > 20 or t1.weight < 200)
+ * and (t2.height < 50 or t2.sales > 100)
+ * }</pre></blockquote>
+ *
+ * <p>new generated predicates are redundant, but they could be pushed down to
+ * scan operator of t1/t2 and reduce the cardinality.
+ *
+ * <p>Note: This rule should only be applied once and it should be used before
+ * {@link CoreRules#FILTER_INTO_JOIN} and {@link 
CoreRules#JOIN_CONDITION_PUSH}.
+ * In order to avoid it interacting with other expression-related rules and 
causing
+ * an infinite loop, it is recommended to use it alone in HepPlanner first,
+ * and then do predicate pushdown.
+ *
+ * @see CoreRules#EXPAND_FILTER_DISJUNCTION_FOR_TABLE
+ * @see CoreRules#EXPAND_JOIN_DISJUNCTION_FOR_TABLE
+ */
[email protected]
+public class ExpandDisjunctionForTableRule
+    extends RelRule<ExpandDisjunctionForTableRule.Config>
+    implements TransformationRule {
+
+  /**
+   * Creates a ExpandDisjunctionForTableRule.
+   */
+  protected ExpandDisjunctionForTableRule(Config config) {
+    super(config);
+  }
+
+  @Override public void onMatch(RelOptRuleCall call) {
+    config.matchHandler().accept(this, call);
+  }
+
+  /**
+   * Expand predicates for condition of a {@link Filter} or {@link Join}.
+   *
+   * @param condition   Condition to be expanded in Filter or Join
+   * @param relNode     The Filter or Join node
+   * @param fieldList   The field list of the Filter or Join inputs. Build the 
referenced columns
+   *                    in the predicate as RexInputRef and find out which 
table the RexInputRef
+   *                    comes from {@link 
RelMetadataQuery#getExpressionLineage}
+   * @param relBuilder  Builder
+   * @param mq          RelMetadataQuery, which is used to get the expression 
lineage
+   *
+   * @return Expanded predicates
+   */
+  private RexNode apply(
+      RexNode condition,
+      RelNode relNode,
+      List<RelDataTypeField> fieldList,
+      RelBuilder relBuilder,
+      RelMetadataQuery mq) {
+    final Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef = new 
HashMap<>();
+
+    ImmutableBitSet columnBits = RelOptUtil.InputFinder.bits(condition);
+    if (columnBits.isEmpty()) {
+      return condition;
+    }
+
+    // Trace which table does the column referenced in the condition come from
+    for (int columnBit : columnBits.asList()) {
+      Set<RexNode> exprLineage =
+          mq.getExpressionLineage(
+              relNode,
+              RexInputRef.of(columnBit, fieldList));
+      // If mq.getExpressionLineage cannot get result, skip it
+      if (exprLineage == null) {
+        continue;
+      }
+      Set<RexTableInputRef.RelTableRef> relTableRefs =
+          RexUtil.gatherTableReferences(Lists.newArrayList(exprLineage));
+      // If the column comes from multiple tables, skip it
+      if (relTableRefs.isEmpty() || relTableRefs.size() > 1) {
+        continue;
+      }
+      inputRefToTableRef.put(columnBit, relTableRefs.iterator().next());
+    }
+
+    ExpandDisjunctionForTableHelper expandHelper =
+        new ExpandDisjunctionForTableHelper(inputRefToTableRef, relBuilder, 
config.bloat());
+    Map<RexTableInputRef.RelTableRef, RexNode> expandResult = 
expandHelper.expand(condition);
+
+    RexNode newCondition = condition;
+    for (RexNode expandCondition : expandResult.values()) {
+      newCondition = relBuilder.and(newCondition, expandCondition);
+    }
+    return newCondition;
+  }
+
+  private static void matchFilter(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Filter filter = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    RexNode newCondition =
+        rule.apply(
+            filter.getCondition(),
+            filter,
+            filter.getRowType().getFieldList(),
+            relBuilder,
+            mq);
+    if (newCondition.equals(filter.getCondition())) {
+      return;
+    }
+    Filter newFilter = filter.copy(filter.getTraitSet(), filter.getInput(), 
newCondition);
+    call.transformTo(newFilter);
+  }
+
+  private static void matchJoin(ExpandDisjunctionForTableRule rule, 
RelOptRuleCall call) {
+    Join join = call.rel(0);
+    RelMetadataQuery mq = call.getMetadataQuery();
+    RelBuilder relBuilder = call.builder();
+
+    List<RelDataTypeField> fieldList =
+        Lists.newArrayList(join.getLeft().getRowType().getFieldList());
+    fieldList.addAll(join.getRight().getRowType().getFieldList());
+    RexNode newCondition =
+        rule.apply(
+            join.getCondition(),
+            join,
+            fieldList,
+            relBuilder,
+            mq);
+    if (newCondition.equals(join.getCondition())) {
+      return;
+    }
+    Join newJoin =
+        join.copy(
+            join.getTraitSet(),
+            newCondition,
+            join.getLeft(),
+            join.getRight(),
+            join.getJoinType(),
+            join.isSemiJoinDone());
+    call.transformTo(newJoin);
+  }
+
+  /**
+   * Helper class to expand predicates.
+   */
+  private static class ExpandDisjunctionForTableHelper {
+
+    private final Map<Integer, RexTableInputRef.RelTableRef> 
inputRefToTableRef;
+
+    private final RelBuilder relBuilder;
+
+    private final int maxNodeCount;
+
+    // Used to record the number of redundant expressions expanded.
+    private int currentCount;
+
+    private ExpandDisjunctionForTableHelper(
+        Map<Integer, RexTableInputRef.RelTableRef> inputRefToTableRef,
+        RelBuilder relBuilder,
+        int maxNodeCount) {
+      this.inputRefToTableRef = inputRefToTableRef;
+      this.relBuilder = relBuilder;
+      this.maxNodeCount = maxNodeCount;
+    }
+
+    private Map<RexTableInputRef.RelTableRef, RexNode> expand(RexNode 
condition) {
+      try {
+        this.currentCount = 0;
+        return expandDeep(condition);
+      } catch (OverLimitException e) {
+        return new HashMap<>();
+      }
+    }
+
+    /**
+     * Expand predicates recursively that can be pushed down to single table.
+     *
+     * @param condition   Predicate to be expanded
+     * @return  Additional predicates that can be pushed down for each table
+     */
+    private Map<RexTableInputRef.RelTableRef, RexNode> expandDeep(RexNode 
condition) {
+      Map<RexTableInputRef.RelTableRef, RexNode> additionalConditions = new 
HashMap<>();
+
+      ImmutableBitSet inputRefs = RelOptUtil.InputFinder.bits(condition);
+      if (inputRefs.isEmpty()) {
+        return additionalConditions;
+      }
+
+      RexTableInputRef.RelTableRef tableRef = 
inputRefsBelongToOneTable(inputRefs);
+      // The condition already belongs to one table, return it directly
+      if (tableRef != null) {
+        checkExpandCount(condition.nodeCount());
+        additionalConditions.put(tableRef, condition);
+        return additionalConditions;
+      }
+
+      // Recursively expand the expression according to whether it is a 
conjunction
+      // or a disjunction. If it is neither a disjunction nor a conjunction, 
it cannot
+      // be expanded further and an empty Map is returned.
+      switch (condition.getKind()) {
+      case AND:
+        List<RexNode> andOperands = RexUtil.flattenAnd(((RexCall) 
condition).getOperands());
+        for (RexNode andOperand : andOperands) {
+          Map<RexTableInputRef.RelTableRef, RexNode> operandResult = 
expandDeep(andOperand);
+          mergeAnd(additionalConditions, operandResult);
+        }
+        break;
+      case OR:
+        List<RexNode> orOperands = RexUtil.flattenOr(((RexCall) 
condition).getOperands());
+        additionalConditions.putAll(expandDeep(orOperands.get(0)));
+        for (int i = 1; i < orOperands.size(); i++) {
+          Map<RexTableInputRef.RelTableRef, RexNode> operandResult =
+              expandDeep(orOperands.get(i));
+          mergeOr(additionalConditions, operandResult);
+
+          if (additionalConditions.isEmpty()) {
+            break;
+          }
+        }
+        break;
+      default:
+        break;
+      }
+
+      return additionalConditions;
+    }
+
+    private RexTableInputRef.@Nullable RelTableRef inputRefsBelongToOneTable(
+        ImmutableBitSet inputRefs) {
+      RexTableInputRef.RelTableRef tableRef = 
inputRefToTableRef.get(inputRefs.nth(0));
+      if (tableRef == null) {
+        return null;
+      }
+      for (int inputBit : inputRefs.asList()) {
+        RexTableInputRef.RelTableRef inputBitTableRef = 
inputRefToTableRef.get(inputBit);
+        if (!tableRef.equals(inputBitTableRef)) {
+          return null;
+        }
+      }
+      return tableRef;
+    }
+
+    /**
+     * For additional predicates of each operand in conjunction, all of them 
should be retained and
+     * use 'AND' to combine expressions. For example:
+     *
+     * <p>baseMap: {t1: p1, t2: p2}
+     *
+     * <p>forMergeMap: {t1: p11, t3: p3}
+     *
+     * <p>result: {t1: p1 AND p11, t2: p2, t3: p3}
+     *
+     * @param baseMap       Additional predicates that current conjunction has 
already saved
+     * @param forMergeMap   Additional predicates that current operand has 
expanded
+     */
+    private void mergeAnd(
+        Map<RexTableInputRef.RelTableRef, RexNode> baseMap,
+        Map<RexTableInputRef.RelTableRef, RexNode> forMergeMap) {
+      for (Map.Entry<RexTableInputRef.RelTableRef, RexNode> entry : 
forMergeMap.entrySet()) {
+        RexNode mergedRex =
+            relBuilder.and(
+                entry.getValue(),
+                baseMap.getOrDefault(entry.getKey(), 
relBuilder.literal(true)));
+        int oriCount = entry.getValue().nodeCount()
+            + (baseMap.containsKey(entry.getKey())
+                ? baseMap.get(entry.getKey()).nodeCount()
+                : 0);
+        checkExpandCount(mergedRex.nodeCount() - oriCount);
+        baseMap.put(entry.getKey(), mergedRex);
+      }
+    }
+
+    /**
+     * Only if all operands in disjunction have additional predicates for 
table t1, we use 'OR'

Review Comment:
   see my comments for javadoc above



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