Merge pull request #44241 from ClibMouse/bugfix/subtract-subseconds

Bring interval subtraction from datetime in line with addition

src/Functions/FunctionDateOrDateTimeAddInterval.h

@@ -685,37 +685,27 @@ public:
         }
         else if constexpr (std::is_same_v<ResultDataType, DataTypeDateTime64>)
         {
-            if (typeid_cast<const DataTypeDateTime64 *>(arguments[0].type.get()))
+            static constexpr auto target_scale = std::invoke(
+                []() -> std::optional<UInt32>
+                {
+                    if constexpr (std::is_base_of_v<AddNanosecondsImpl, Transform>)
+                        return 9;
+                    else if constexpr (std::is_base_of_v<AddMicrosecondsImpl, Transform>)
+                        return 6;
+                    else if constexpr (std::is_base_of_v<AddMillisecondsImpl, Transform>)
+                        return 3;
+
+                    return {};
+                });
+
+            auto timezone = extractTimeZoneNameFromFunctionArguments(arguments, 2, 0);
+            if (const auto* datetime64_type = typeid_cast<const DataTypeDateTime64 *>(arguments[0].type.get()))
             {
-                const auto & datetime64_type = assert_cast<const DataTypeDateTime64 &>(*arguments[0].type);
+                const auto from_scale = datetime64_type->getScale();
-
+                return std::make_shared<DataTypeDateTime64>(std::max(from_scale, target_scale.value_or(from_scale)), std::move(timezone));
-                auto from_scale = datetime64_type.getScale();
-                auto scale = from_scale;
-
-                if (std::is_same_v<Transform, AddNanosecondsImpl>)
-                    scale = 9;
-                else if (std::is_same_v<Transform, AddMicrosecondsImpl>)
-                    scale = 6;
-                else if (std::is_same_v<Transform, AddMillisecondsImpl>)
-                    scale = 3;
-
-                scale = std::max(scale, from_scale);
-
-                return std::make_shared<DataTypeDateTime64>(scale, extractTimeZoneNameFromFunctionArguments(arguments, 2, 0));
             }
-            else
-            {
-                auto scale = DataTypeDateTime64::default_scale;
 
-                if (std::is_same_v<Transform, AddNanosecondsImpl>)
+            return std::make_shared<DataTypeDateTime64>(target_scale.value_or(DataTypeDateTime64::default_scale), std::move(timezone));
-                    scale = 9;
-                else if (std::is_same_v<Transform, AddMicrosecondsImpl>)
-                    scale = 6;
-                else if (std::is_same_v<Transform, AddMillisecondsImpl>)
-                    scale = 3;
-
-                return std::make_shared<DataTypeDateTime64>(scale, extractTimeZoneNameFromFunctionArguments(arguments, 2, 0));
-            }
         }
 
         throw Exception(ErrorCodes::LOGICAL_ERROR, "Unexpected result type in datetime add interval function");

tests/queries/0_stateless/02207_subseconds_intervals.reference

@@ -60,3 +60,19 @@ test add[...]seconds()
 2220-12-12 12:12:12.124
 2220-12-12 12:12:12.121
 2220-12-12 12:12:12.124456
+test subtract[...]seconds()
+- test nanoseconds
+2022-12-31 23:59:59.999999999
+2022-12-31 23:59:59.999999900
+2023-01-01 00:00:00.000000001
+2023-01-01 00:00:00.000000100
+- test microseconds
+2022-12-31 23:59:59.999999
+2022-12-31 23:59:59.999900
+2023-01-01 00:00:00.000001
+2023-01-01 00:00:00.000100
+- test milliseconds
+2022-12-31 23:59:59.999
+2022-12-31 23:59:59.900
+2023-01-01 00:00:00.001
+2023-01-01 00:00:00.100

tests/queries/0_stateless/02207_subseconds_intervals.sql

@@ -92,3 +92,22 @@ select addMilliseconds(toDateTime64('1930-12-12 12:12:12.123456', 6), 1); -- Bel
 select addMilliseconds(toDateTime64('2220-12-12 12:12:12.123', 3), 1); -- Above normal range, source scale matches result
 select addMilliseconds(toDateTime64('2220-12-12 12:12:12.12', 2), 1); -- Above normal range, source scale less than result
 select addMilliseconds(toDateTime64('2220-12-12 12:12:12.123456', 6), 1); -- Above normal range, source scale greater than result
+
+select 'test subtract[...]seconds()';
+select '- test nanoseconds';
+select subtractNanoseconds(toDateTime64('2023-01-01 00:00:00.0000000', 7, 'UTC'), 1);
+select subtractNanoseconds(toDateTime64('2023-01-01 00:00:00.0000000', 7, 'UTC'), 100);
+select subtractNanoseconds(toDateTime64('2023-01-01 00:00:00.0000000', 7, 'UTC'), -1);
+select subtractNanoseconds(toDateTime64('2023-01-01 00:00:00.0000000', 7, 'UTC'), -100);
+
+select '- test microseconds';
+select subtractMicroseconds(toDateTime64('2023-01-01 00:00:00.0000', 4, 'UTC'), 1);
+select subtractMicroseconds(toDateTime64('2023-01-01 00:00:00.0000', 4, 'UTC'), 100);
+select subtractMicroseconds(toDateTime64('2023-01-01 00:00:00.0000', 4, 'UTC'), -1);
+select subtractMicroseconds(toDateTime64('2023-01-01 00:00:00.0000', 4, 'UTC'), -100);
+
+select '- test milliseconds';
+select subtractMilliseconds(toDateTime64('2023-01-01 00:00:00.0', 1, 'UTC'), 1);
+select subtractMilliseconds(toDateTime64('2023-01-01 00:00:00.0', 1, 'UTC'), 100);
+select subtractMilliseconds(toDateTime64('2023-01-01 00:00:00.0', 1, 'UTC'), -1);
+select subtractMilliseconds(toDateTime64('2023-01-01 00:00:00.0', 1, 'UTC'), -100);