From 322dc2a1049bf7ec4b649919843b417eb6cfb651 Mon Sep 17 00:00:00 2001
From: Pxl <pxl290@qq.com>
Date: Mon, 30 Jan 2023 18:01:26 +0800
Subject: [PATCH] [Bug](function) fix now(int)
 use_default_implementation_for_nulls && fix dround signature (#16238)

---
 .../functions/function_date_or_datetime_computation.cpp   | 2 +-
 .../vec/functions/function_date_or_datetime_computation.h | 8 ++++++--
 be/src/vec/functions/math.cpp                             | 1 +
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/be/src/vec/functions/function_date_or_datetime_computation.cpp b/be/src/vec/functions/function_date_or_datetime_computation.cpp
index abaef68c4c..8df40c1fc3 100644
--- a/be/src/vec/functions/function_date_or_datetime_computation.cpp
+++ b/be/src/vec/functions/function_date_or_datetime_computation.cpp
@@ -89,7 +89,7 @@ using FunctionLocalTimestamp =
         FunctionCurrentDateOrDateTime<CurrentDateTimeImpl<LocalTimestampFunctionName, false>>;
 
 using FunctionNowWithPrecision =
-        FunctionCurrentDateOrDateTime<CurrentDateTimeImpl<NowFunctionName, true>>;
+        FunctionCurrentDateOrDateTime<CurrentDateTimeImpl<NowFunctionName, true>, false>;
 using FunctionCurrentTimestampWithPrecision =
         FunctionCurrentDateOrDateTime<CurrentDateTimeImpl<CurrentTimestampFunctionName, true>>;
 using FunctionLocalTimeWithPrecision =
diff --git a/be/src/vec/functions/function_date_or_datetime_computation.h b/be/src/vec/functions/function_date_or_datetime_computation.h
index eba6d17fc7..a4d51c972c 100644
--- a/be/src/vec/functions/function_date_or_datetime_computation.h
+++ b/be/src/vec/functions/function_date_or_datetime_computation.h
@@ -583,7 +583,7 @@ public:
     }
 };
 
-template <typename FunctionImpl>
+template <typename FunctionImpl, bool DefaultNullable = true>
 class FunctionCurrentDateOrDateTime : public IFunction {
 public:
     static constexpr bool has_variadic_argument =
@@ -596,6 +596,8 @@ public:
 
     size_t get_number_of_arguments() const override { return 0; }
 
+    bool use_default_implementation_for_nulls() const override { return DefaultNullable; }
+
     DataTypePtr get_return_type_impl(const ColumnsWithTypeAndName& arguments) const override {
         return std::make_shared<typename FunctionImpl::ReturnType>();
     }
@@ -603,7 +605,9 @@ public:
     bool is_variadic() const override { return true; }
 
     DataTypes get_variadic_argument_types_impl() const override {
-        if constexpr (has_variadic_argument) return FunctionImpl::get_variadic_argument_types();
+        if constexpr (has_variadic_argument) {
+            return FunctionImpl::get_variadic_argument_types();
+        }
         return {};
     }
 
diff --git a/be/src/vec/functions/math.cpp b/be/src/vec/functions/math.cpp
index 9efcd45d07..e4294323da 100644
--- a/be/src/vec/functions/math.cpp
+++ b/be/src/vec/functions/math.cpp
@@ -431,6 +431,7 @@ void register_function_math(SimpleFunctionFactory& factory) {
     REGISTER_ROUND_FUNCTIONS(DecimalRoundTwoImpl)
     REGISTER_ROUND_FUNCTIONS(DoubleRoundOneImpl)
     REGISTER_ROUND_FUNCTIONS(DoubleRoundTwoImpl)
+    factory.register_alias("round", "dround");
     factory.register_function<FunctionAcos>();
     factory.register_function<FunctionAsin>();
     factory.register_function<FunctionAtan>();