Review

Author: robert-brunel

fdb-record-layer-core/src/main/java/com/apple/foundationdb/record/query/plan/cascades/expressions/ExplodeExpression.java

@@ -56,13 +56,10 @@
  * A table function expression that “explodes” a repeated field into a stream of its values.
  *
  * <p>In the {@code WITH ORDINALITY} variant, it also generates 1-based ordinals of the field values. In this case it
- * produces a struct with fields {@code {_element, _ordinal}} instead of the bare element.
+ * produces a struct with two anonymous fields—the element and the ordinal—instead of the bare element.
  */
 @API(API.Status.EXPERIMENTAL)
 public class ExplodeExpression extends AbstractRelationalExpressionWithoutChildren implements InternalPlannerGraphRewritable {
-    public static final String ELEMENT_FIELD_NAME = "_element";
-    public static final String ORDINAL_FIELD_NAME = "_ordinal";
-
     @Nonnull
     private final Value collectionValue;
 
@@ -104,15 +101,15 @@ public Type getElementType() {
     }
 
     /**
-     * Returns the type of the explode result. For the {@code WITH ORDINALITY} variant, builds the
-     * struct result type {@code {_element: elementType, _ordinal: INT}}.
+     * Returns the type of the explode result. For the {@code WITH ORDINALITY} variant, builds an anonymous-field
+     * struct result type holding the element and the 1-based ordinal.
      */
     @Nonnull
     public static Type explodeResultType(@Nonnull final Type elementType, boolean withOrdinality) {
         if (withOrdinality) {
             return Type.Record.fromFields(ImmutableList.of(
-                    Type.Record.Field.of(elementType, Optional.of(ELEMENT_FIELD_NAME)),
-                    Type.Record.Field.of(Type.primitiveType(Type.TypeCode.INT, false), Optional.of(ORDINAL_FIELD_NAME))));
+                    Type.Record.Field.of(elementType, Optional.empty()),
+                    Type.Record.Field.of(Type.primitiveType(Type.TypeCode.INT, false), Optional.empty())));
         } else {
             return elementType;
         }
@@ -169,12 +166,12 @@ public boolean equalsWithoutChildren(@Nonnull RelationalExpression otherExpressi
         if (this == otherExpression) {
             return true;
         }
-        if (!(otherExpression instanceof final ExplodeExpression otherExplodeExpression)) {
-            return false;
+        if (otherExpression instanceof final ExplodeExpression other) {
+            return collectionValue.semanticEquals(other.getCollectionValue(), equivalencesMap) &&
+                    isWithOrdinality() == other.isWithOrdinality() &&
+                    semanticEqualsForResults(otherExpression, equivalencesMap);
         }
-        return collectionValue.semanticEquals(otherExplodeExpression.getCollectionValue(), equivalencesMap) &&
-                withOrdinality == otherExplodeExpression.withOrdinality &&
-                semanticEqualsForResults(otherExpression, equivalencesMap);
+        return false;
     }
 
     @Override
@@ -239,8 +236,8 @@ public PlannerGraph rewriteInternalPlannerGraph(@Nonnull final List<? extends Pl
     @Override
     public String toString() {
         return withOrdinality
-                ? collectionValue + " WITH ORDINALITY"
-                : collectionValue.toString();
+               ? collectionValue + " WITH ORDINALITY"
+               : collectionValue.toString();
     }
 
     public static ExplodeExpression explodeField(@Nonnull final Quantifier.ForEach baseQuantifier,

fdb-record-layer-core/src/main/java/com/apple/foundationdb/record/query/plan/cascades/properties/DerivationsProperty.java

@@ -32,7 +32,6 @@
 import com.apple.foundationdb.record.query.plan.cascades.ExpressionProperty;
 import com.apple.foundationdb.record.query.plan.cascades.Reference;
 import com.apple.foundationdb.record.query.plan.cascades.Quantifier;
-import com.apple.foundationdb.record.query.plan.cascades.expressions.ExplodeExpression;
 import com.apple.foundationdb.record.query.plan.cascades.expressions.RelationalExpressionVisitor;
 import com.apple.foundationdb.record.query.plan.cascades.TreeLike;
 import com.apple.foundationdb.record.query.plan.cascades.expressions.RelationalExpression;
@@ -348,10 +347,8 @@ public Derivations visitExplodePlan(@Nonnull final RecordQueryExplodePlan explod
             if (explodePlan.isWithOrdinality()) {
                 final Type ordinalType = Type.primitiveType(Type.TypeCode.INT, false);
                 representative = RecordConstructorValue.ofColumns(List.of(
-                        Column.of(Type.Record.Field.of(elementType, Optional.of(ExplodeExpression.ELEMENT_FIELD_NAME)),
-                                first),
-                        Column.of(Type.Record.Field.of(ordinalType, Optional.of(ExplodeExpression.ORDINAL_FIELD_NAME)),
-                                new ThrowsValue(ordinalType))));
+                        Column.of(Type.Record.Field.of(elementType, Optional.empty()), first),
+                        Column.of(Type.Record.Field.of(ordinalType, Optional.empty()), new ThrowsValue(ordinalType))));
             } else {
                 representative = first;
             }

fdb-record-layer-core/src/main/java/com/apple/foundationdb/record/query/plan/plans/RecordQueryExplodePlan.java

@@ -75,8 +75,8 @@
  * value to Java type {@code List<?>}, and then produces one {@link QueryResult} datum per array element.
  *
  * <p>In the {@code WITH ORDINALITY} variant, {@code EXPLODE} also generates ordinals of the array elements. In this
- * case the plan produces a {@link DynamicMessage} struct with fields {@code {_element, _ordinal}} instead of
- * the bare element. The ordinals are 1-based per the SQL standard (Foundation, Section 4.10.2).
+ * case the plan produces a {@link DynamicMessage} struct with two anonymous fields (the element and the ordinal)
+ * instead of the bare element. The ordinals are 1-based per the SQL standard (Foundation, Section 4.10.2).
  *
  * @see RecordQueryFlatMapPlan
  */
@@ -85,7 +85,7 @@ public class RecordQueryExplodePlan extends AbstractRelationalExpressionWithoutC
     private static final ObjectPlanHash BASE_HASH = new ObjectPlanHash("Record-Query-Explode-Plan");
 
     /**
-     * The collection value. Must evaluate to a {@code List<?>}.
+     * The collection value. Must evaluate to an array type.
      */
     @Nonnull
     private final Value collectionValue;
@@ -145,7 +145,7 @@ public <M extends Message> RecordCursor<QueryResult> executePlan(@Nonnull final
                     .skipThenLimit(executeProperties.getSkip(), executeProperties.getReturnedRowLimit());
         }
 
-        // In the WITH ORDINALITY case, produce a struct {_element, _ordinal} per list element, with 1-based ordinals.
+        // In the WITH ORDINALITY case, produce a struct (element, ordinal) per list element, with 1-based ordinals.
         final Type elementType = getElementType();
         final var resultType = (Type.Record) getExplodeResultType();
         final TypeRepository typeRepository = context.getTypeRepository();
@@ -256,7 +256,10 @@ public Value getResultValue() {
     @Nonnull
     @Override
     public Set<Type> getDynamicTypes() {
-        return collectionValue.getDynamicTypes();
+        return ImmutableSet.<Type>builder()
+                .addAll(collectionValue.getDynamicTypes())
+                .addAll(getResultValue().getDynamicTypes())
+                .build();
     }
 
     @Nonnull
@@ -276,9 +279,8 @@ public boolean equalsWithoutChildren(@Nonnull RelationalExpression otherExpressi
             return false;
         }
         final var otherExplodePlan = (RecordQueryExplodePlan)otherExpression;
-
         return collectionValue.semanticEquals(otherExplodePlan.getCollectionValue(), equivalencesMap) &&
-                withOrdinality == otherExplodePlan.withOrdinality &&
+                isWithOrdinality() == otherExplodePlan.isWithOrdinality() &&
                 semanticEqualsForResults(otherExpression, equivalencesMap);
     }
 

fdb-record-layer-core/src/main/java/com/apple/foundationdb/record/query/plan/plans/RecordQueryFlatMapPlan.java

@@ -66,12 +66,6 @@
  * A {@code FLATMAP} plan node. {@code FLATMAP} implements correlated lateral joins by executing an inner plan for each
  * row produced by a “driving” outer plan and combining the results. The inner plan may reference the outer row via
  * correlation. The outer and inner rows are combined by applying the {@link #resultValue} expression.
- *
- * <p>{@code FLATMAP} and {@code EXPLODE} are the runtime backbone of array unnesting. For example, for a simple
- * unnesting query {@code SELECT … FROM T, T.ARR AS A}, the outer plan scans {@code T} and the inner plan explodes the
- * array {@code T.ARR}.
- *
- * @see RecordQueryExplodePlan
  */
 @API(API.Status.INTERNAL)
 public class RecordQueryFlatMapPlan extends AbstractRelationalExpressionWithChildren implements RecordQueryPlanWithChildren, ExplainPlannerGraphRewritable, InternalPlannerGraphRewritable {

fdb-record-layer-core/src/test/java/com/apple/foundationdb/record/query/plan/plans/ExplodePlanTest.java

@@ -287,8 +287,8 @@ void derivationsPreserveCollectionCorrelation() {
     }
 
     /**
-     * Verify that {@link ExplodeExpression#getDynamicTypes()} registers the synthesized {@code {_element, _ordinal}}
-     * struct as a dynamic type in the WITH ORDINALITY variant.
+     * Verify that {@link ExplodeExpression#getDynamicTypes()} registers the synthesized (element, ordinal) struct as
+     * a dynamic type in the WITH ORDINALITY variant.
      */
     @Test
     void dynamicTypesIncludeOrdinalityStruct() {

fdb-relational-core/src/main/java/com/apple/foundationdb/relational/recordlayer/query/LogicalOperator.java

@@ -317,7 +317,7 @@ private static LogicalOperator generateCorrelatedFieldAccess(@Nonnull Expression
 
         final ImmutableList.Builder<Expression> attributesBuilder = ImmutableList.builder();
         if (atAlias.isPresent()) {
-            // With AT, the `ExplodeExpression` produces a struct {_element, _ordinal}. Use `FieldValue` accessors.
+            // With AT, the `ExplodeExpression` produces a struct (element, ordinal). Use `FieldValue` accessors.
             final Type elementType = explode.getElementType();
             attributesBuilder.add(new Expression(alias, DataTypeUtils.toRelationalType(elementType),
                     FieldValue.ofOrdinalNumber(flowedObjectValue, 0)));

yaml-tests/src/test/resources/array-join-at.metrics.binpb

@@ -4,19 +4,19 @@ array-join-at:
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 AS q1 RETURN (q0.id AS
         id, q1 AS val) }
     task_count: 160
-    task_total_time_ms: 67
+    task_total_time_ms: 51
     transform_count: 47
-    transform_time_ms: 51
+    transform_time_ms: 38
     transform_yield_count: 13
     insert_time_ms: 0
     insert_new_count: 15
     insert_reused_count: 0
 -   query: EXPLAIN SELECT "id", "val", "at" FROM T1, T1."arr1" AS "val" AT "at"
     ref: array-join-at.yamsql:56
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q1
-        RETURN (q0.id AS id, q1._element AS val, q1._ordinal AS at) }
+        RETURN (q0.id AS id, q1._0 AS val, q1._1 AS at) }
     task_count: 160
-    task_total_time_ms: 15
+    task_total_time_ms: 13
     transform_count: 47
     transform_time_ms: 6
     transform_yield_count: 13
@@ -26,11 +26,11 @@ array-join-at:
 -   query: EXPLAIN SELECT "id", "at" FROM T1, T1."arr1" AT "at"
     ref: array-join-at.yamsql:93
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q1
-        RETURN (q0.id AS id, q1._ordinal AS at) }
+        RETURN (q0.id AS id, q1._1 AS at) }
     task_count: 160
     task_total_time_ms: 12
     transform_count: 47
-    transform_time_ms: 4
+    transform_time_ms: 5
     transform_yield_count: 13
     insert_time_ms: 0
     insert_new_count: 15
@@ -40,12 +40,11 @@ array-join-at:
         AT "at"
     ref: array-join-at.yamsql:104
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q1
-        RETURN (q0.id + @c17 - @c17 AS id, q1._ordinal AS at, q1._element AS val)
-        }
+        RETURN (q0.id + @c17 - @c17 AS id, q1._1 AS at, q1._0 AS val) }
     task_count: 188
     task_total_time_ms: 13
     transform_count: 51
-    transform_time_ms: 6
+    transform_time_ms: 5
     transform_yield_count: 15
     insert_time_ms: 0
     insert_new_count: 21
@@ -55,24 +54,24 @@ array-join-at:
     ref: array-join-at.yamsql:115
     explain: EXPLODE array((@c11 AS id, array(@c14) AS arr), (@c19 AS id, array(@c22,
         @c24, @c26) AS arr)) | FLATMAP q0 -> { EXPLODE q0.arr WITH ORDINALITY AS q1
-        RETURN (q0.id AS id, q1._element AS val, q1._ordinal AS at) }
+        RETURN (q0.id AS id, q1._0 AS val, q1._1 AS at) }
     task_count: 238
-    task_total_time_ms: 15
+    task_total_time_ms: 16
     transform_count: 71
-    transform_time_ms: 4
+    transform_time_ms: 5
     transform_yield_count: 14
-    insert_time_ms: 1
+    insert_time_ms: 0
     insert_new_count: 24
     insert_reused_count: 0
 -   query: EXPLAIN SELECT "id", "at" + 10 AS "at_plus_10" FROM T1, T1."arr1" AS "val"
         AT "at"
     ref: array-join-at.yamsql:140
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q1
-        RETURN (q0.id AS id, q1._ordinal + @c5 AS at_plus_10) }
+        RETURN (q0.id AS id, q1._1 + @c5 AS at_plus_10) }
     task_count: 160
-    task_total_time_ms: 7
+    task_total_time_ms: 5
     transform_count: 47
-    transform_time_ms: 3
+    transform_time_ms: 2
     transform_yield_count: 13
     insert_time_ms: 0
     insert_new_count: 15
@@ -81,26 +80,26 @@ array-join-at:
         WHERE "val" > 201
     ref: array-join-at.yamsql:150
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1_nn WITH ORDINALITY |
-        FILTER _._element GREATER_THAN promote(@c19 AS INT) AS q1 RETURN (q0.id AS
-        id, q1._element AS val, q1._ordinal AS at) }
+        FILTER _._0 GREATER_THAN promote(@c19 AS INT) AS q1 RETURN (q0.id AS id, q1._0
+        AS val, q1._1 AS at) }
     task_count: 253
-    task_total_time_ms: 18
+    task_total_time_ms: 15
     transform_count: 83
     transform_time_ms: 5
     transform_yield_count: 17
-    insert_time_ms: 2
+    insert_time_ms: 1
     insert_new_count: 27
     insert_reused_count: 1
 -   query: EXPLAIN SELECT "id", "val", "at" FROM T1, T1."arr1_nn" AS "val" AT "at"
         WHERE "at" + 1 = 3
     ref: array-join-at.yamsql:158
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1_nn WITH ORDINALITY |
-        FILTER _._ordinal + @c19 EQUALS promote(@c21 AS INT) AS q1 RETURN (q0.id AS
-        id, q1._element AS val, q1._ordinal AS at) }
+        FILTER _._1 + @c19 EQUALS promote(@c21 AS INT) AS q1 RETURN (q0.id AS id,
+        q1._0 AS val, q1._1 AS at) }
     task_count: 253
     task_total_time_ms: 12
     transform_count: 83
-    transform_time_ms: 6
+    transform_time_ms: 5
     transform_yield_count: 17
     insert_time_ms: 1
     insert_new_count: 27
@@ -110,10 +109,10 @@ array-join-at:
     ref: array-join-at.yamsql:172
     explain: SCAN([IS T2]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY | FLATMAP
         q1 -> { EXPLODE q0.arr2 WITH ORDINALITY AS q2 RETURN (q1 AS _0, q2 AS _1)
-        } AS q3 RETURN (q0.id AS id, q3._0._ordinal AS at1, q3._0._element AS val1,
-        q3._1._ordinal AS at2, q3._1._element AS val2) }
+        } AS q3 RETURN (q0.id AS id, q3._0._1 AS at1, q3._0._0 AS val1, q3._1._1 AS
+        at2, q3._1._0 AS val2) }
     task_count: 253
-    task_total_time_ms: 11
+    task_total_time_ms: 10
     transform_count: 89
     transform_time_ms: 5
     transform_yield_count: 18
@@ -125,12 +124,12 @@ array-join-at:
     ref: array-join-at.yamsql:183
     explain: SCAN([IS T2]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY | FLATMAP
         q1 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q2 RETURN (q1 AS _0, q2 AS _1)
-        } AS q3 RETURN (q0.id AS id, q3._0._element AS val1, q3._0._ordinal AS at1,
-        q3._1._element AS val2, q3._1._ordinal AS at2) }
+        } AS q3 RETURN (q0.id AS id, q3._0._0 AS val1, q3._0._1 AS at1, q3._1._0 AS
+        val2, q3._1._1 AS at2) }
     task_count: 242
-    task_total_time_ms: 8
+    task_total_time_ms: 7
     transform_count: 88
-    transform_time_ms: 4
+    transform_time_ms: 3
     transform_yield_count: 17
     insert_time_ms: 0
     insert_new_count: 25
@@ -139,10 +138,10 @@ array-join-at:
         FROM T1, T1."arr1" AS "arr1_val" AT "at"
     ref: array-join-at.yamsql:202
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY AS q1
-        RETURN (q0.id AS id, q1._ordinal AS at, q1._element AS arr1_val, q0.arr1_nn[q1._ordinal>
-        AS arr1_nn_val) }
+        RETURN (q0.id AS id, q1._1 AS at, q1._0 AS arr1_val, q0.arr1_nn[q1._1> AS
+        arr1_nn_val) }
     task_count: 160
-    task_total_time_ms: 4
+    task_total_time_ms: 5
     transform_count: 47
     transform_time_ms: 2
     transform_yield_count: 13
@@ -155,23 +154,23 @@ array-join-at:
     ref: array-join-at.yamsql:219
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1 WITH ORDINALITY | FLATMAP
         q1 -> { SCAN([IS T1, EQUALS q0.id]) | FLATMAP q2 -> { EXPLODE q2.arr1_nn WITH
-        ORDINALITY | FILTER _._element EQUALS q1._element AS q3 RETURN q3 } AS q3
-        RETURN (q3 AS _0, q1 AS _1) } AS q5 RETURN (q0.id AS id, q5._1._ordinal AS
-        at, q5._1._element AS val, q5._0._element AS val2) }
+        ORDINALITY | FILTER _._0 EQUALS q1._0 AS q3 RETURN q3 } AS q3 RETURN (q3 AS
+        _0, q1 AS _1) } AS q5 RETURN (q0.id AS id, q5._1._1 AS at, q5._1._0 AS val,
+        q5._0._0 AS val2) }
     task_count: 6364
-    task_total_time_ms: 298
+    task_total_time_ms: 272
     transform_count: 3065
-    transform_time_ms: 106
+    transform_time_ms: 102
     transform_yield_count: 295
-    insert_time_ms: 43
+    insert_time_ms: 37
     insert_new_count: 757
     insert_reused_count: 133
 -   query: EXPLAIN SELECT T2."id", "val1", "at1", "val2" FROM T2, T2."arr1" AS "val1"
         AT "at1", T2."arr2" AS "val2"
     ref: array-join-at.yamsql:258
     explain: SCAN([IS T2]) | FLATMAP q0 -> { EXPLODE q0.arr2 | FLATMAP q1 -> { EXPLODE
         q0.arr1 WITH ORDINALITY AS q2 RETURN (q2 AS _0, q1 AS _1) } AS q3 RETURN (q0.id
-        AS id, q3._0._element AS val1, q3._0._ordinal AS at1, q3._1 AS val2) }
+        AS id, q3._0._0 AS val1, q3._0._1 AS at1, q3._1 AS val2) }
     task_count: 253
     task_total_time_ms: 4
     transform_count: 89
@@ -185,11 +184,11 @@ array-join-at:
     ref: array-join-at.yamsql:298
     explain: '[IN arrayDistinct(promote(@c21 AS ARRAY(LONG)))] | INJOIN q0 -> { SCAN([IS
         T1, EQUALS q0]) | FLATMAP q1 -> { EXPLODE q1.arr1_nn WITH ORDINALITY AS q2
-        RETURN (q1.id AS id, q2._element AS val, q2._ordinal AS at) } }'
+        RETURN (q1.id AS id, q2._0 AS val, q2._1 AS at) } }'
     task_count: 1164
-    task_total_time_ms: 26
+    task_total_time_ms: 31
     transform_count: 453
-    transform_time_ms: 11
+    transform_time_ms: 14
     transform_yield_count: 68
     insert_time_ms: 2
     insert_new_count: 140
@@ -198,12 +197,12 @@ array-join-at:
         WHERE "at" IN (1, 2)
     ref: array-join-at.yamsql:310
     explain: SCAN([IS T1]) | FLATMAP q0 -> { EXPLODE q0.arr1_nn WITH ORDINALITY |
-        FILTER _._ordinal IN @c19 AS q1 RETURN (q0.id AS id, q1._element AS val, q1._ordinal
-        AS at) }
+        FILTER _._1 IN @c19 AS q1 RETURN (q0.id AS id, q1._0 AS val, q1._1 AS at)
+        }
     task_count: 1058
     task_total_time_ms: 15
     transform_count: 422
-    transform_time_ms: 5
+    transform_time_ms: 6
     transform_yield_count: 52
     insert_time_ms: 1
     insert_new_count: 115