CALCITE-4913 Correlated variables in a select list are not deduplicated

cassandra/src/main/java/org/apache/calcite/adapter/cassandra/CassandraProject.java

@@ -21,19 +21,23 @@
 import org.apache.calcite.plan.RelOptPlanner;
 import org.apache.calcite.plan.RelTraitSet;
 import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.CorrelationId;
 import org.apache.calcite.rel.core.Project;
 import org.apache.calcite.rel.metadata.RelMetadataQuery;
 import org.apache.calcite.rel.type.RelDataType;
 import org.apache.calcite.rex.RexNode;
 import org.apache.calcite.util.Pair;
 
+import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 /**
  * Implementation of {@link org.apache.calcite.rel.core.Project}
@@ -42,13 +46,15 @@
 public class CassandraProject extends Project implements CassandraRel {
   public CassandraProject(RelOptCluster cluster, RelTraitSet traitSet,
       RelNode input, List<? extends RexNode> projects, RelDataType rowType) {
-    super(cluster, traitSet, ImmutableList.of(), input, projects, rowType);
+    super(cluster, traitSet, ImmutableList.of(), input, projects, rowType, ImmutableSet.of());
     assert getConvention() == CassandraRel.CONVENTION;
     assert getConvention() == input.getConvention();
   }
 
   @Override public Project copy(RelTraitSet traitSet, RelNode input,
-      List<RexNode> projects, RelDataType rowType) {
+      List<RexNode> projects, RelDataType rowType, Set<CorrelationId> variablesSet) {
+    Preconditions.checkArgument(variablesSet.isEmpty(),
+        "Correlated scalar subqueries are not supported");
     return new CassandraProject(getCluster(), traitSet, input, projects,
         rowType);
   }

cassandra/src/main/java/org/apache/calcite/adapter/cassandra/CassandraRules.java

@@ -258,7 +258,8 @@ public interface CassandraFilterRuleConfig extends RelRule.Config {
   public static class CassandraProjectRule extends CassandraConverterRule {
     /** Default configuration. */
     private static final Config DEFAULT_CONFIG = Config.INSTANCE
-        .withConversion(LogicalProject.class, Convention.NONE,
+        .withConversion(LogicalProject.class, p -> p.getCorrelVariable() == null
+                && p.getVariablesSet().isEmpty(), Convention.NONE,
             CassandraRel.CONVENTION, "CassandraProjectRule")
         .withRuleFactory(CassandraProjectRule::new);
 

core/src/main/java/org/apache/calcite/adapter/enumerable/EnumerableProject.java

@@ -20,6 +20,7 @@
 import org.apache.calcite.plan.RelTraitSet;
 import org.apache.calcite.rel.RelCollationTraitDef;
 import org.apache.calcite.rel.RelNode;
+import org.apache.calcite.rel.core.CorrelationId;
 import org.apache.calcite.rel.core.Project;
 import org.apache.calcite.rel.metadata.RelMdCollation;
 import org.apache.calcite.rel.metadata.RelMetadataQuery;
@@ -28,11 +29,14 @@
 import org.apache.calcite.util.Pair;
 import org.apache.calcite.util.Util;
 
+import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.List;
+import java.util.Set;
 
 /** Implementation of {@link org.apache.calcite.rel.core.Project} in
  * {@link org.apache.calcite.adapter.enumerable.EnumerableConvention enumerable calling convention}. */
@@ -54,7 +58,7 @@ public EnumerableProject(
       RelNode input,
       List<? extends RexNode> projects,
       RelDataType rowType) {
-    super(cluster, traitSet, ImmutableList.of(), input, projects, rowType);
+    super(cluster, traitSet, ImmutableList.of(), input, projects, rowType, ImmutableSet.of());
     assert getConvention() instanceof EnumerableConvention;
   }
 
@@ -80,7 +84,9 @@ public static EnumerableProject create(final RelNode input,
   }
 
   @Override public EnumerableProject copy(RelTraitSet traitSet, RelNode input,
-      List<RexNode> projects, RelDataType rowType) {
+      List<RexNode> projects, RelDataType rowType, Set<CorrelationId> variablesSet) {
+    Preconditions.checkArgument(variablesSet.isEmpty(),
+        "Correlated scalar subqueries are not supported");
     return new EnumerableProject(getCluster(), traitSet, input,
         projects, rowType);
   }

core/src/main/java/org/apache/calcite/adapter/enumerable/EnumerableProjectRule.java

@@ -32,7 +32,8 @@ class EnumerableProjectRule extends ConverterRule {
   /** Default configuration. */
   static final Config DEFAULT_CONFIG = Config.INSTANCE
       .as(Config.class)
-      .withConversion(LogicalProject.class, p -> !p.containsOver(),
+      .withConversion(LogicalProject.class, p -> !p.containsOver()
+              && p.getCorrelVariable() == null && p.getVariablesSet().isEmpty(),
           Convention.NONE, EnumerableConvention.INSTANCE,
           "EnumerableProjectRule")
       .withRuleFactory(EnumerableProjectRule::new);

core/src/main/java/org/apache/calcite/adapter/enumerable/EnumerableRelFactories.java

@@ -26,6 +26,8 @@
 import org.apache.calcite.rex.RexUtil;
 import org.apache.calcite.sql.validate.SqlValidatorUtil;
 
+import com.google.common.base.Preconditions;
+
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.List;
@@ -68,7 +70,10 @@ private static class ProjectFactoryImpl
       implements org.apache.calcite.rel.core.RelFactories.ProjectFactory {
     @Override public RelNode createProject(RelNode input, List<RelHint> hints,
         List<? extends RexNode> childExprs,
-        @Nullable List<? extends @Nullable String> fieldNames) {
+        @Nullable List<? extends @Nullable String> fieldNames,
+        Set<CorrelationId> variablesSet) {
+      Preconditions.checkArgument(variablesSet.isEmpty(),
+          "Correlated scalar subqueries are not supported");
       final RelDataType rowType =
           RexUtil.createStructType(input.getCluster().getTypeFactory(), childExprs,
               fieldNames, SqlValidatorUtil.F_SUGGESTER);

core/src/main/java/org/apache/calcite/adapter/jdbc/JdbcRules.java

@@ -73,6 +73,7 @@
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.slf4j.Logger;
@@ -96,7 +97,9 @@ private JdbcRules() {
   protected static final Logger LOGGER = CalciteTrace.getPlannerTracer();
 
   static final RelFactories.ProjectFactory PROJECT_FACTORY =
-      (input, hints, projects, fieldNames) -> {
+      (input, hints, projects, fieldNames, variablesSet) -> {
+        Preconditions.checkArgument(variablesSet.isEmpty(),
+            "JdbcProject does not allow variables");
         final RelOptCluster cluster = input.getCluster();
         final RelDataType rowType =
             RexUtil.createStructType(cluster.getTypeFactory(), projects,
@@ -532,7 +535,7 @@ public JdbcProject(
         RelNode input,
         List<? extends RexNode> projects,
         RelDataType rowType) {
-      super(cluster, traitSet, ImmutableList.of(), input, projects, rowType);
+      super(cluster, traitSet, ImmutableList.of(), input, projects, rowType, ImmutableSet.of());
       assert getConvention() instanceof JdbcConvention;
     }
 
@@ -544,7 +547,9 @@ public JdbcProject(RelOptCluster cluster, RelTraitSet traitSet,
     }
 
     @Override public JdbcProject copy(RelTraitSet traitSet, RelNode input,
-        List<RexNode> projects, RelDataType rowType) {
+        List<RexNode> projects, RelDataType rowType, Set<CorrelationId> variablesSet) {
+      Preconditions.checkArgument(variablesSet.isEmpty(),
+          "Correlated scalar subqueries are not supported");
       return new JdbcProject(getCluster(), traitSet, input, projects, rowType);
     }
 

core/src/main/java/org/apache/calcite/interpreter/Bindables.java

@@ -78,6 +78,7 @@
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.immutables.value.Value;
@@ -376,7 +377,8 @@ public static BindableFilter create(final RelNode input,
   public static class BindableProjectRule extends ConverterRule {
     /** Default configuration. */
     public static final Config DEFAULT_CONFIG = Config.INSTANCE
-        .withConversion(LogicalProject.class, p -> !p.containsOver(),
+        .withConversion(LogicalProject.class, p -> !p.containsOver()
+            && p.getCorrelVariable() == null && p.getVariablesSet().isEmpty(),
             Convention.NONE, BindableConvention.INSTANCE,
             "BindableProjectRule")
         .withRuleFactory(BindableProjectRule::new);
@@ -403,12 +405,14 @@ protected BindableProjectRule(Config config) {
   public static class BindableProject extends Project implements BindableRel {
     public BindableProject(RelOptCluster cluster, RelTraitSet traitSet,
         RelNode input, List<? extends RexNode> projects, RelDataType rowType) {
-      super(cluster, traitSet, ImmutableList.of(), input, projects, rowType);
+      super(cluster, traitSet, ImmutableList.of(), input, projects, rowType, ImmutableSet.of());
       assert getConvention() instanceof BindableConvention;
     }
 
     @Override public BindableProject copy(RelTraitSet traitSet, RelNode input,
-        List<RexNode> projects, RelDataType rowType) {
+        List<RexNode> projects, RelDataType rowType, Set<CorrelationId> variablesSet) {
+      Preconditions.checkArgument(variablesSet.isEmpty(),
+          "Correlated scalar subqueries are not supported");
       return new BindableProject(getCluster(), traitSet, input,
           projects, rowType);
     }

core/src/main/java/org/apache/calcite/plan/RelOptUtil.java

@@ -885,6 +885,7 @@ public static RelNode createCastRel(
     List<RexNode> castExps;
     RelNode input;
     List<RelHint> hints = ImmutableList.of();
+    Set<CorrelationId> variablesSet = ImmutableSet.of();
     if (rel instanceof Project) {
       // No need to create another project node if the rel
       // is already a project.
@@ -894,6 +895,7 @@ public static RelNode createCastRel(
           castRowType,
           ((Project) rel).getProjects());
       input = rel.getInput(0);
+      variablesSet = project.getVariablesSet();
       hints = project.getHints();
     } else {
       castExps = RexUtil.generateCastExpressions(
@@ -905,11 +907,11 @@ public static RelNode createCastRel(
     if (rename) {
       // Use names and types from castRowType.
       return projectFactory.createProject(input, hints, castExps,
-          castRowType.getFieldNames());
+          castRowType.getFieldNames(), variablesSet);
     } else {
       // Use names from rowType, types from castRowType.
       return projectFactory.createProject(input, hints, castExps,
-          rowType.getFieldNames());
+          rowType.getFieldNames(), variablesSet);
     }
   }
 

core/src/main/java/org/apache/calcite/rel/RelNode.java

@@ -152,9 +152,6 @@ public interface RelNode extends RelOptNode, Cloneable {
    * expression but also used and therefore not available to parents of this
    * relational expression.
    *
-   * <p>Note: only {@link org.apache.calcite.rel.core.Correlate} should set
-   * variables.
-   *
    * @return Names of variables which are set in this relational
    *   expression
    */