[CALCITE-5862] Incorrect spark semantics of array function when eleme…

…nts have Numeric and Character types
apache · Aug 1, 2023 · 9846350 · 9846350
1 parent 3ab8003
commit 9846350
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Showing 2 changed files with 43 additions and 4 deletions.
diff --git a/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java b/core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java
@@ -955,10 +955,41 @@ static RelDataType deriveTypeSplit(SqlOperatorBinding operatorBinding,
           .withKind(SqlKind.CONCAT_WS_MSSQL);
 
   private static RelDataType arrayReturnType(SqlOperatorBinding opBinding) {
-    RelDataType type =
-        opBinding.getOperandCount() > 0
-            ? ReturnTypes.LEAST_RESTRICTIVE.inferReturnType(opBinding)
-            : opBinding.getTypeFactory().createUnknownType();
+    final List<RelDataType> operandTypes = opBinding.collectOperandTypes();
+
+    // only numeric & character types check
+    boolean hasNumeric = false;
+    boolean hasCharacter = false;
+    for (RelDataType type : operandTypes) {
+      SqlTypeFamily family = type.getSqlTypeName().getFamily();
+      requireNonNull(family, "array element type family");
+      switch (family) {
+      case NUMERIC:
+        hasNumeric = true;
+        break;
+      case CHARACTER:
+        hasCharacter = true;
+        break;
+      default:
+        break;
+      }
+    }
+
+    RelDataType type;
+    boolean useCharacterTypes = hasNumeric && hasCharacter;
+    if (useCharacterTypes) {
+      List<RelDataType> characterTypes =
+          // may include NULL literal
+          operandTypes.stream().filter(
+              t -> t.getSqlTypeName().getFamily() != SqlTypeFamily.NUMERIC)
+              .collect(Collectors.toList());
+      type = opBinding.getTypeFactory().leastRestrictive(characterTypes);
+    } else {
+      type =
+          opBinding.getOperandCount() > 0
+              ? ReturnTypes.LEAST_RESTRICTIVE.inferReturnType(opBinding)
+              : opBinding.getTypeFactory().createUnknownType();
+    }
     requireNonNull(type, "inferred array element type");
     return SqlTypeUtil.createArrayType(opBinding.getTypeFactory(), type, false);
   }

diff --git a/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java b/testkit/src/main/java/org/apache/calcite/test/SqlOperatorTest.java
@@ -8894,6 +8894,14 @@ private static void checkArrayConcatAggFuncFails(SqlOperatorFixture t) {
         "[null, foo]", "CHAR(3) ARRAY NOT NULL");
     f2.checkScalar("array(null)",
         "[null]", "NULL ARRAY NOT NULL");
+    f2.checkScalar("array(1, 2, 'Hi')",
+        "[1, 2, Hi]", "CHAR(2) NOT NULL ARRAY NOT NULL");
+    f2.checkScalar("array(1, 2, 'Hi', 'Hello')",
+        "[1, 2, Hi, Hello]", "CHAR(5) NOT NULL ARRAY NOT NULL");
+    f2.checkScalar("array(1, 2, 'Hi', null)",
+        "[1, 2, Hi, null]", "CHAR(2) ARRAY NOT NULL");
+    f2.checkScalar("array(1, 2, 'Hi', cast(null as char(10)))",
+        "[1, 2, Hi, null]", "CHAR(10) ARRAY NOT NULL");
   }
 
   /**