add multi-value string object vector matcher and expression vector object selectors

processing/src/main/java/org/apache/druid/query/filter/vector/MultiValueStringObjectVectorValueMatcher.java

@@ -0,0 +1,128 @@
+/*
+ * 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.druid.query.filter.vector;
+
+import org.apache.druid.math.expr.ExprEval;
+import org.apache.druid.math.expr.ExpressionType;
+import org.apache.druid.query.filter.DruidObjectPredicate;
+import org.apache.druid.query.filter.DruidPredicateFactory;
+import org.apache.druid.segment.column.ColumnType;
+import org.apache.druid.segment.vector.VectorObjectSelector;
+
+import javax.annotation.Nullable;
+import java.util.List;
+import java.util.Objects;
+
+public class MultiValueStringObjectVectorValueMatcher implements VectorValueMatcherFactory
+{
+  protected final VectorObjectSelector selector;
+
+  public MultiValueStringObjectVectorValueMatcher(final VectorObjectSelector selector)
+  {
+    this.selector = selector;
+  }
+
+  @Override
+  public VectorValueMatcher makeMatcher(@Nullable String value)
+  {
+    return new BaseVectorValueMatcher(selector)
+    {
+      final VectorMatch match = VectorMatch.wrap(new int[selector.getMaxVectorSize()]);
+
+      @Override
+      public ReadableVectorMatch match(final ReadableVectorMatch mask, boolean includeUnknown)
+      {
+        final Object[] vector = selector.getObjectVector();
+        final int[] selection = match.getSelection();
+
+        int numRows = 0;
+
+        for (int i = 0; i < mask.getSelectionSize(); i++) {
+          final int rowNum = mask.getSelection()[i];
+          final Object val = vector[rowNum];
+          if (val instanceof List) {
+            for (Object o : (List) val) {
+              if ((o == null && includeUnknown) || Objects.equals(value, o)) {
+                selection[numRows++] = rowNum;
+                break;
+              }
+            }
+          } else {
+            if ((val == null && includeUnknown) || Objects.equals(value, val)) {
+              selection[numRows++] = rowNum;
+            }
+          }
+        }
+
+        match.setSelectionSize(numRows);
+        return match;
+      }
+    };
+  }
+
+  @Override
+  public VectorValueMatcher makeMatcher(Object matchValue, ColumnType matchValueType)
+  {
+    final ExprEval<?> eval = ExprEval.ofType(ExpressionType.fromColumnType(matchValueType), matchValue);
+    final ExprEval<?> castForComparison = ExprEval.castForEqualityComparison(eval, ExpressionType.STRING);
+    if (castForComparison == null || castForComparison.asString() == null) {
+      return VectorValueMatcher.allFalseObjectMatcher(selector);
+    }
+    return makeMatcher(castForComparison.asString());
+  }
+
+  @Override
+  public VectorValueMatcher makeMatcher(DruidPredicateFactory predicateFactory)
+  {
+    final DruidObjectPredicate<String> predicate = predicateFactory.makeStringPredicate();
+
+    return new BaseVectorValueMatcher(selector)
+    {
+      final VectorMatch match = VectorMatch.wrap(new int[selector.getMaxVectorSize()]);
+
+      @Override
+      public ReadableVectorMatch match(final ReadableVectorMatch mask, boolean includeUnknown)
+      {
+        final Object[] vector = selector.getObjectVector();
+        final int[] selection = match.getSelection();
+
+        int numRows = 0;
+
+        for (int i = 0; i < mask.getSelectionSize(); i++) {
+          final int rowNum = mask.getSelection()[i];
+          Object val = vector[rowNum];
+          if (val instanceof List) {
+            for (Object o : (List) val) {
+              if (predicate.apply((String) o).matches(includeUnknown)) {
+                selection[numRows++] = rowNum;
+                break;
+              }
+            }
+          } else if (predicate.apply((String) val).matches(includeUnknown)) {
+            selection[numRows++] = rowNum;
+          }
+        }
+
+        match.setSelectionSize(numRows);
+        return match;
+      }
+    };
+  }
+}

processing/src/main/java/org/apache/druid/query/filter/vector/VectorValueMatcherColumnProcessorFactory.java

@@ -99,6 +99,9 @@ public VectorValueMatcherFactory makeObjectProcessor(
   )
   {
     if (capabilities.is(ValueType.STRING)) {
+      if (capabilities.hasMultipleValues().isTrue()) {
+        return new MultiValueStringObjectVectorValueMatcher(selector);
+      }
       return new StringObjectVectorValueMatcher(selector);
     }
     return new ObjectVectorValueMatcher(selector);

processing/src/main/java/org/apache/druid/segment/filter/ExpressionFilter.java

@@ -121,18 +121,18 @@ public VectorValueMatcher makeVectorMatcher(VectorColumnSelectorFactory factory)
       case STRING:
         return VectorValueMatcherColumnProcessorFactory.instance().makeObjectProcessor(
             ColumnCapabilitiesImpl.createSimpleSingleValueStringColumnCapabilities(),
-            ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr)
+            ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr, null)
         ).makeMatcher(predicateFactory);
       case ARRAY:
         return VectorValueMatcherColumnProcessorFactory.instance().makeObjectProcessor(
             ColumnCapabilitiesImpl.createDefault().setType(ExpressionType.toColumnType(outputType)).setHasNulls(true),
-            ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr)
+            ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr, null)
         ).makeMatcher(predicateFactory);
       default:
         if (ExpressionType.NESTED_DATA.equals(outputType)) {
           return VectorValueMatcherColumnProcessorFactory.instance().makeObjectProcessor(
               ColumnCapabilitiesImpl.createDefault().setType(ExpressionType.toColumnType(outputType)).setHasNulls(true),
-              ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr)
+              ExpressionVectorSelectors.makeVectorObjectSelector(factory, theExpr, null)
           ).makeMatcher(predicateFactory);
         }
         throw new UOE("Vectorized expression matchers not implemented for type: [%s]", outputType);

processing/src/main/java/org/apache/druid/segment/virtual/ExpressionMultiValueDimensionSelector.java

@@ -76,10 +76,14 @@ String getValue(ExprEval evaluated)
     return evaluated.asString();
   }
 
+  @Nullable
   List<String> getArrayAsList(ExprEval evaluated)
   {
     assert evaluated.isArray();
     //noinspection ConstantConditions
+    if (evaluated.asArray() == null) {
+      return null;
+    }
     return Arrays.stream(evaluated.asArray())
                  .map(Evals::asString)
                  .collect(Collectors.toList());
@@ -133,6 +137,9 @@ public boolean matches(boolean includeUnknown)
         ExprEval evaluated = getEvaluated();
         if (evaluated.isArray()) {
           List<String> array = getArrayAsList(evaluated);
+          if (array == null) {
+            return includeUnknown || value == null;
+          }
           return array.stream().anyMatch(x -> (includeUnknown && x == null) || Objects.equals(x, value));
         }
         final String rowValue = getValue(evaluated);
@@ -159,6 +166,9 @@ public boolean matches(boolean includeUnknown)
         final DruidObjectPredicate<String> predicate = predicateFactory.makeStringPredicate();
         if (evaluated.isArray()) {
           List<String> array = getArrayAsList(evaluated);
+          if (array == null) {
+            return predicate.apply(null).matches(includeUnknown);
+          }
           return array.stream().anyMatch(x -> predicate.apply(x).matches(includeUnknown));
         }
         final String rowValue = getValue(evaluated);

processing/src/main/java/org/apache/druid/segment/virtual/ExpressionVectorMultiValueStringObjectSelector.java

@@ -0,0 +1,81 @@
+/*
+ * 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.druid.segment.virtual;
+
+import com.google.common.base.Preconditions;
+import org.apache.druid.math.expr.Expr;
+import org.apache.druid.math.expr.vector.ExprVectorProcessor;
+import org.apache.druid.segment.vector.ReadableVectorInspector;
+import org.apache.druid.segment.vector.VectorObjectSelector;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+
+import java.util.Arrays;
+
+public class ExpressionVectorMultiValueStringObjectSelector implements VectorObjectSelector
+{
+  private final Expr.VectorInputBinding bindings;
+  private final ExprVectorProcessor<?> processor;
+
+  @MonotonicNonNull
+  private Object[] cached;
+  private int currentId = ReadableVectorInspector.NULL_ID;
+
+  public ExpressionVectorMultiValueStringObjectSelector(
+      ExprVectorProcessor<?> processor,
+      Expr.VectorInputBinding bindings
+  )
+  {
+    this.processor = Preconditions.checkNotNull(processor, "processor");
+    this.bindings = Preconditions.checkNotNull(bindings, "bindings");
+    this.cached = new Object[bindings.getMaxVectorSize()];
+  }
+
+  @Override
+  public Object[] getObjectVector()
+  {
+    if (bindings.getCurrentVectorId() != currentId) {
+      currentId = bindings.getCurrentVectorId();
+      final Object[] tmp = processor.evalVector(bindings).getObjectVector();
+      for (int i = 0; i < bindings.getCurrentVectorSize(); i++) {
+        Object[] tmpi = (Object[]) tmp[i];
+        if (tmpi == null) {
+          cached[i] = null;
+        } else if (tmpi.length == 1) {
+          cached[i] = tmpi[0];
+        } else {
+          cached[i] = Arrays.asList(tmpi);
+        }
+      }
+    }
+    return cached;
+  }
+
+  @Override
+  public int getMaxVectorSize()
+  {
+    return bindings.getMaxVectorSize();
+  }
+
+  @Override
+  public int getCurrentVectorSize()
+  {
+    return bindings.getCurrentVectorSize();
+  }
+}

processing/src/main/java/org/apache/druid/segment/virtual/ExpressionVectorSelectors.java

@@ -21,6 +21,7 @@
 
 import com.google.common.base.Preconditions;
 import org.apache.druid.math.expr.Expr;
+import org.apache.druid.math.expr.ExprEval;
 import org.apache.druid.math.expr.ExprType;
 import org.apache.druid.math.expr.ExpressionType;
 import org.apache.druid.math.expr.InputBindings;
@@ -33,6 +34,8 @@
 import org.apache.druid.segment.column.ColumnCapabilities;
 import org.apache.druid.segment.column.ColumnType;
 import org.apache.druid.segment.column.RowSignature;
+import org.apache.druid.segment.column.Types;
+import org.apache.druid.segment.column.ValueType;
 import org.apache.druid.segment.vector.ConstantVectorSelectors;
 import org.apache.druid.segment.vector.ReadableVectorInspector;
 import org.apache.druid.segment.vector.SingleValueDimensionVectorSelector;
@@ -94,21 +97,32 @@ public static VectorValueSelector makeVectorValueSelector(
 
   public static VectorObjectSelector makeVectorObjectSelector(
       VectorColumnSelectorFactory factory,
-      Expr expression
+      Expr expression,
+      @Nullable ColumnType outputTypeHint
   )
   {
     final ExpressionPlan plan = ExpressionPlanner.plan(factory, expression);
     Preconditions.checkArgument(plan.is(ExpressionPlan.Trait.VECTORIZABLE));
 
     if (plan.isConstant()) {
+      final ExprEval<?> eval = plan.getExpression().eval(InputBindings.nilBindings());
+      if (Types.is(outputTypeHint, ValueType.STRING) && eval.type().isArray()) {
+        return ConstantVectorSelectors.vectorObjectSelector(
+            factory.getReadableVectorInspector(),
+            ExpressionSelectors.coerceEvalToObjectOrList(eval)
+        );
+      }
       return ConstantVectorSelectors.vectorObjectSelector(
           factory.getReadableVectorInspector(),
-          plan.getExpression().eval(InputBindings.nilBindings()).valueOrDefault()
+          eval.valueOrDefault()
       );
     }
 
     final Expr.VectorInputBinding bindings = createVectorBindings(plan.getAnalysis(), factory);
     final ExprVectorProcessor<?> processor = plan.getExpression().asVectorProcessor(bindings);
+    if (Types.is(outputTypeHint, ValueType.STRING) && processor.getOutputType().isArray()) {
+      return new ExpressionVectorMultiValueStringObjectSelector(processor, bindings);
+    }
     return new ExpressionVectorObjectSelector(processor, bindings);
   }
 

processing/src/main/java/org/apache/druid/segment/virtual/ExpressionVirtualColumn.java

@@ -238,7 +238,7 @@ public VectorObjectSelector makeVectorObjectSelector(String columnName, VectorCo
       return factory.makeObjectSelector(parsedExpression.get().getBindingIfIdentifier());
     }
 
-    return ExpressionVectorSelectors.makeVectorObjectSelector(factory, parsedExpression.get());
+    return ExpressionVectorSelectors.makeVectorObjectSelector(factory, parsedExpression.get(), expression.outputType);
   }
 
   @Nullable

processing/src/test/java/org/apache/druid/segment/filter/BaseFilterTest.java

@@ -163,7 +163,11 @@ public abstract class BaseFilterTest extends InitializedNullHandlingTest
           new NestedFieldVirtualColumn("nested", "$.l0", "nested.l0", ColumnType.LONG),
           new NestedFieldVirtualColumn("nested", "$.arrayLong", "nested.arrayLong", ColumnType.LONG_ARRAY),
           new NestedFieldVirtualColumn("nested", "$.arrayDouble", "nested.arrayDouble", ColumnType.DOUBLE_ARRAY),
-          new NestedFieldVirtualColumn("nested", "$.arrayString", "nested.arrayString", ColumnType.STRING_ARRAY)
+          new NestedFieldVirtualColumn("nested", "$.arrayString", "nested.arrayString", ColumnType.STRING_ARRAY),
+          new ExpressionVirtualColumn("arrayLongAsMvd", "array_to_mv(arrayLong)", ColumnType.STRING, TestExprMacroTable.INSTANCE),
+          new ExpressionVirtualColumn("arrayDoubleAsMvd", "array_to_mv(arrayDouble)", ColumnType.STRING, TestExprMacroTable.INSTANCE),
+          new ExpressionVirtualColumn("arrayStringAsMvd", "array_to_mv(arrayString)", ColumnType.STRING, TestExprMacroTable.INSTANCE),
+          new ExpressionVirtualColumn("arrayConstantAsMvd", "array_to_mv(array(1,2,3))", ColumnType.STRING, TestExprMacroTable.INSTANCE)
       )
   );