From 2a14168075d74062196e259582cdf4007b01da60 Mon Sep 17 00:00:00 2001
From: kevinyhzou <kevinyunhe8@gmail.com>
Date: Fri, 31 May 2024 16:44:31 +0800
Subject: [PATCH 1/2] improve least/greatest by allow nullable numberic fields
 compare

---
 src/Functions/LeastGreatestGeneric.h |  2 +-
 tests/performance/least_greatest.xml | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 tests/performance/least_greatest.xml

diff --git a/src/Functions/LeastGreatestGeneric.h b/src/Functions/LeastGreatestGeneric.h
index 9073f14d679..07efb1904eb 100644
--- a/src/Functions/LeastGreatestGeneric.h
+++ b/src/Functions/LeastGreatestGeneric.h
@@ -111,7 +111,7 @@ public:
             argument_types.push_back(argument.type);
 
         /// More efficient specialization for two numeric arguments.
-        if (arguments.size() == 2 && isNumber(arguments[0].type) && isNumber(arguments[1].type))
+        if (arguments.size() == 2 && isNumber(removeNullable(arguments[0].type)) && isNumber(removeNullable(arguments[1].type)))
             return std::make_unique<FunctionToFunctionBaseAdaptor>(SpecializedFunction::create(context), argument_types, return_type);
 
         return std::make_unique<FunctionToFunctionBaseAdaptor>(
diff --git a/tests/performance/least_greatest.xml b/tests/performance/least_greatest.xml
new file mode 100644
index 00000000000..522bcd9004d
--- /dev/null
+++ b/tests/performance/least_greatest.xml
@@ -0,0 +1,10 @@
+<test>
+    <create_query>CREATE TABLE test (id Int32, x1 Nullable(Int32), x2 Nullable(Float32)) ENGINE = MergeTree() ORDER BY id</create_query>
+
+    <fill_query>INSERT INTO test SELECT number, number+1, number + 2 FROM numbers(1000000)</fill_query>
+
+    <query tag='LEAST'>SELECT COUNT(1) FROM test WHERE least(x1, x2) > 1</query>
+    <query tag='GREATEST'>SELECT COUNT(1) FROM test WHERE GREATEST(x1, x2) > 1</query>
+    
+    <drop_query>DROP TABLE IF EXISTS test</drop_query>
+</test>
\ No newline at end of file

From 2c28cf80595592b952dfa8c13e173b92b654089f Mon Sep 17 00:00:00 2001
From: kevinyhzou <kevinyunhe8@gmail.com>
Date: Wed, 5 Jun 2024 15:46:59 +0800
Subject: [PATCH 2/2] review fix

---
 src/Functions/LeastGreatestGeneric.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Functions/LeastGreatestGeneric.h b/src/Functions/LeastGreatestGeneric.h
index 07efb1904eb..bbab001b00d 100644
--- a/src/Functions/LeastGreatestGeneric.h
+++ b/src/Functions/LeastGreatestGeneric.h
@@ -123,7 +123,7 @@ public:
         if (types.empty())
             throw Exception(ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH, "Function {} cannot be called without arguments", getName());
 
-        if (types.size() == 2 && isNumber(types[0]) && isNumber(types[1]))
+        if (types.size() == 2 && isNumber(removeNullable(types[0])) && isNumber(removeNullable(types[1])))
             return SpecializedFunction::create(context)->getReturnTypeImpl(types);
 
         return getLeastSupertype(types);