GH-44569: [GLib] Add GArrowDecimal64DataType

c_glib/arrow-glib/basic-data-type.cpp

@@ -114,6 +114,8 @@ G_BEGIN_DECLS
  *
  * #GArrowDecimalDataType is a base class for the decimal data types.
  *
+ * #GArrowDecimal64DataType is a class for the 64-bit decimal data type.
+ *
  * #GArrowDecimal128DataType is a class for the 128-bit decimal data type.
  *
  * #GArrowDecimal256DataType is a class for the 256-bit decimal data type.
@@ -1500,7 +1502,10 @@ garrow_decimal_data_type_class_init(GArrowDecimalDataTypeClass *klass)
 GArrowDecimalDataType *
 garrow_decimal_data_type_new(gint32 precision, gint32 scale, GError **error)
 {
-  if (precision <= garrow_decimal128_data_type_max_precision()) {
+  if (precision <= garrow_decimal64_data_type_max_precision()) {
+    return GARROW_DECIMAL_DATA_TYPE(
+      garrow_decimal64_data_type_new(precision, scale, error));
+  } else if (precision <= garrow_decimal128_data_type_max_precision()) {
     return GARROW_DECIMAL_DATA_TYPE(
       garrow_decimal128_data_type_new(precision, scale, error));
   } else {
@@ -1545,6 +1550,57 @@ garrow_decimal_data_type_get_scale(GArrowDecimalDataType *decimal_data_type)
   return arrow_decimal_type->scale();
 }
 
+G_DEFINE_TYPE(GArrowDecimal64DataType,
+              garrow_decimal64_data_type,
+              GARROW_TYPE_DECIMAL_DATA_TYPE)
+
+static void
+garrow_decimal64_data_type_init(GArrowDecimal64DataType *object)
+{
+}
+
+static void
+garrow_decimal64_data_type_class_init(GArrowDecimal64DataTypeClass *klass)
+{
+}
+
+/**
+ * garrow_decimal64_data_type_max_precision:
+ *
+ * Returns: The max precision of 64-bit decimal data type.
+ *
+ * Since: 19.0.0
+ */
+gint32
+garrow_decimal64_data_type_max_precision()
+{
+  return arrow::Decimal64Type::kMaxPrecision;
+}
+
+/**
+ * garrow_decimal64_data_type_new:
+ * @precision: The precision of decimal data.
+ * @scale: The scale of decimal data.
+ * @error: (nullable): Return location for a #GError or %NULL.
+ *
+ * Returns: (nullable):
+ *   The newly created 64-bit decimal data type on success, %NULL on error.
+ *
+ * Since: 19.0.0
+ */
+GArrowDecimal64DataType *
+garrow_decimal64_data_type_new(gint32 precision, gint32 scale, GError **error)
+{
+  auto arrow_data_type_result = arrow::Decimal64Type::Make(precision, scale);
+  if (garrow::check(error, arrow_data_type_result, "[decimal64-data-type][new]")) {
+    auto arrow_data_type = *arrow_data_type_result;
+    return GARROW_DECIMAL64_DATA_TYPE(
+      g_object_new(GARROW_TYPE_DECIMAL64_DATA_TYPE, "data-type", &arrow_data_type, NULL));
+  } else {
+    return NULL;
+  }
+}
+
 G_DEFINE_TYPE(GArrowDecimal128DataType,
               garrow_decimal128_data_type,
               GARROW_TYPE_DECIMAL_DATA_TYPE)
@@ -2193,6 +2249,9 @@ garrow_data_type_new_raw(std::shared_ptr<arrow::DataType> *arrow_data_type)
   case arrow::Type::type::MAP:
     type = GARROW_TYPE_MAP_DATA_TYPE;
     break;
+  case arrow::Type::type::DECIMAL64:
+    type = GARROW_TYPE_DECIMAL64_DATA_TYPE;
+    break;
   case arrow::Type::type::DECIMAL128:
     type = GARROW_TYPE_DECIMAL128_DATA_TYPE;
     break;

c_glib/arrow-glib/basic-data-type.h

@@ -608,6 +608,26 @@ GARROW_AVAILABLE_IN_ALL
 gint32
 garrow_decimal_data_type_get_scale(GArrowDecimalDataType *decimal_data_type);
 
+#define GARROW_TYPE_DECIMAL64_DATA_TYPE (garrow_decimal64_data_type_get_type())
+GARROW_AVAILABLE_IN_19_0
+G_DECLARE_DERIVABLE_TYPE(GArrowDecimal64DataType,
+                         garrow_decimal64_data_type,
+                         GARROW,
+                         DECIMAL64_DATA_TYPE,
+                         GArrowDecimalDataType)
+struct _GArrowDecimal64DataTypeClass
+{
+  GArrowDecimalDataTypeClass parent_class;
+};
+
+GARROW_AVAILABLE_IN_19_0
+gint32
+garrow_decimal64_data_type_max_precision();
+
+GARROW_AVAILABLE_IN_19_0
+GArrowDecimal64DataType *
+garrow_decimal64_data_type_new(gint32 precision, gint32 scale, GError **error);
+
 #define GARROW_TYPE_DECIMAL128_DATA_TYPE (garrow_decimal128_data_type_get_type())
 GARROW_AVAILABLE_IN_ALL
 G_DECLARE_DERIVABLE_TYPE(GArrowDecimal128DataType,

c_glib/arrow-glib/type.cpp

@@ -78,6 +78,8 @@ garrow_type_from_raw(arrow::Type::type type)
     return GARROW_TYPE_MONTH_INTERVAL;
   case arrow::Type::type::INTERVAL_DAY_TIME:
     return GARROW_TYPE_DAY_TIME_INTERVAL;
+  case arrow::Type::type::DECIMAL64:
+    return GARROW_TYPE_DECIMAL64;
   case arrow::Type::type::DECIMAL128:
     return GARROW_TYPE_DECIMAL128;
   case arrow::Type::type::DECIMAL256:

c_glib/arrow-glib/type.h

@@ -50,6 +50,8 @@ G_BEGIN_DECLS
  * @GARROW_TYPE_TIME64: Exact time encoded with int64, supporting micro- or nanoseconds
  * @GARROW_TYPE_MONTH_INTERVAL: YEAR_MONTH interval in SQL style.
  * @GARROW_TYPE_DAY_TIME_INTERVAL: DAY_TIME interval in SQL style.
+ * @GARROW_TYPE_DECIMAL64: Precision- and scale-based decimal
+ *   type with 64-bit. Storage type depends on the parameters.
  * @GARROW_TYPE_DECIMAL128: Precision- and scale-based decimal
  *   type with 128-bit. Storage type depends on the parameters.
  * @GARROW_TYPE_DECIMAL256: Precision- and scale-based decimal
@@ -113,6 +115,8 @@ typedef enum {
   GARROW_TYPE_LARGE_LIST,
   GARROW_TYPE_MONTH_DAY_NANO_INTERVAL,
   GARROW_TYPE_RUN_END_ENCODED,
+  /* TODO: Remove = 44 when we add STRING_VIEW..DECIMAL32. */
+  GARROW_TYPE_DECIMAL64 = 44,
 } GArrowType;
 
 /**

c_glib/test/test-decimal128-data-type.rb

@@ -42,8 +42,8 @@ def test_scale
   end
 
   def test_decimal_data_type_new
-    assert_equal(Arrow::Decimal128DataType.new(8, 2),
-                 Arrow::DecimalDataType.new(8, 2))
+    assert_equal(Arrow::Decimal128DataType.new(19, 2),
+                 Arrow::DecimalDataType.new(19, 2))
   end
 
   def test_invalid_precision

c_glib/test/test-decimal64-data-type.rb

@@ -0,0 +1,54 @@
+# 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.
+
+class TestDecimal64DataType < Test::Unit::TestCase
+  def test_type
+    data_type = Arrow::Decimal64DataType.new(2, 0)
+    assert_equal(Arrow::Type::DECIMAL64, data_type.id)
+  end
+
+  def test_name
+    data_type = Arrow::Decimal64DataType.new(2, 0)
+    assert_equal("decimal64", data_type.name)
+  end
+
+  def test_to_s
+    data_type = Arrow::Decimal64DataType.new(2, 0)
+    assert_equal("decimal64(2, 0)", data_type.to_s)
+  end
+
+  def test_precision
+    data_type = Arrow::Decimal64DataType.new(8, 2)
+    assert_equal(8, data_type.precision)
+  end
+
+  def test_scale
+    data_type = Arrow::Decimal64DataType.new(8, 2)
+    assert_equal(2, data_type.scale)
+  end
+
+  def test_decimal_data_type_new
+    assert_equal(Arrow::Decimal64DataType.new(18, 2),
+                 Arrow::DecimalDataType.new(18, 2))
+  end
+
+  def test_invalid_precision
+    assert_raise(Arrow::Error::Invalid) do
+      Arrow::Decimal64DataType.new(19, 1)
+    end
+  end
+end