New analyzer pass to optimize in single value

src/Analyzer/Passes/ConvertInToEqualPass.cpp

@@ -0,0 +1,73 @@
+#include <Analyzer/ColumnNode.h>
+#include <Analyzer/ConstantNode.h>
+#include <Analyzer/FunctionNode.h>
+#include <Analyzer/InDepthQueryTreeVisitor.h>
+#include <Analyzer/Passes/ConvertInToEqualPass.h>
+#include <Functions/equals.h>
+#include <Functions/notEquals.h>
+
+namespace DB
+{
+
+class ConvertInToEqualPassVisitor : public InDepthQueryTreeVisitorWithContext<ConvertInToEqualPassVisitor>
+{
+public:
+    using Base = InDepthQueryTreeVisitorWithContext<ConvertInToEqualPassVisitor>;
+    using Base::Base;
+
+    void enterImpl(QueryTreeNodePtr & node)
+    {
+        static const std::unordered_map<String, String> MAPPING = {
+            {"in", "equals"},
+            {"notIn", "notEquals"}
+        };
+        auto * func_node = node->as<FunctionNode>();
+        if (!func_node
+            || !MAPPING.contains(func_node->getFunctionName())
+            || func_node->getArguments().getNodes().size() != 2)
+            return ;
+        auto args = func_node->getArguments().getNodes();
+        auto * column_node = args[0]->as<ColumnNode>();
+        auto * constant_node = args[1]->as<ConstantNode>();
+        if (!column_node || !constant_node)
+            return ;
+        // IN multiple values is not supported
+        if (constant_node->getValue().getType() == Field::Types::Which::Tuple
+            || constant_node->getValue().getType() == Field::Types::Which::Array)
+            return ;
+        // x IN null not equivalent to x = null
+        if (constant_node->getValue().isNull())
+            return ;
+        auto result_func_name = MAPPING.at(func_node->getFunctionName());
+        auto equal = std::make_shared<FunctionNode>(result_func_name);
+        QueryTreeNodes arguments{column_node->clone(), constant_node->clone()};
+        equal->getArguments().getNodes() = std::move(arguments);
+        FunctionOverloadResolverPtr resolver;
+        bool decimal_check_overflow = getContext()->getSettingsRef().decimal_check_overflow;
+        if (result_func_name == "equals")
+        {
+            resolver = createInternalFunctionEqualOverloadResolver(decimal_check_overflow);
+        }
+        else
+        {
+            resolver = createInternalFunctionNotEqualOverloadResolver(decimal_check_overflow);
+        }
+        try
+        {
+            equal->resolveAsFunction(resolver);
+        }
+        catch (...)
+        {
+            // When function resolver fails, we should not replace the function node
+            return;
+        }
+        node = equal;
+    }
+};
+
+void ConvertInToEqualPass::run(QueryTreeNodePtr & query_tree_node, ContextPtr context)
+{
+    ConvertInToEqualPassVisitor visitor(std::move(context));
+    visitor.visit(query_tree_node);
+}
+}

src/Analyzer/Passes/ConvertInToEqualPass.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <Analyzer/IQueryTreePass.h>
+
+namespace DB
+{
+/** Optimize `in` to `equals` if possible.
+  * 1. convert in single value to equal
+  * Example: SELECT * from test where x IN (1);
+  * Result: SELECT * from test where x = 1;
+  *
+  * 2. convert not in single value to notEqual
+  * Example: SELECT * from test where x NOT IN (1);
+  * Result: SELECT * from test where x != 1;
+  *
+  * If value is null or tuple, do not convert.
+  */
+class ConvertInToEqualPass final : public IQueryTreePass
+{
+public:
+    String getName() override { return "ConvertInToEqualPass"; }
+
+    String getDescription() override { return "Convert in to equal"; }
+
+    void run(QueryTreeNodePtr & query_tree_node, ContextPtr context) override;
+};
+}

src/Analyzer/QueryTreePassManager.cpp

@@ -28,6 +28,7 @@
 #include <Analyzer/Passes/MultiIfToIfPass.h>
 #include <Analyzer/Passes/IfConstantConditionPass.h>
 #include <Analyzer/Passes/IfChainToMultiIfPass.h>
+#include <Analyzer/Passes/ConvertInToEqualPass.h>
 #include <Analyzer/Passes/OrderByTupleEliminationPass.h>
 #include <Analyzer/Passes/NormalizeCountVariantsPass.h>
 #include <Analyzer/Passes/AggregateFunctionsArithmericOperationsPass.h>
@@ -263,6 +264,7 @@ void addQueryTreePasses(QueryTreePassManager & manager, bool only_analyze)
     manager.addPass(std::make_unique<SumIfToCountIfPass>());
     manager.addPass(std::make_unique<RewriteArrayExistsToHasPass>());
     manager.addPass(std::make_unique<NormalizeCountVariantsPass>());
+    manager.addPass(std::make_unique<ConvertInToEqualPass>());
 
     /// should before AggregateFunctionsArithmericOperationsPass
     manager.addPass(std::make_unique<AggregateFunctionOfGroupByKeysPass>());

src/Functions/CMakeLists.txt

@@ -14,6 +14,8 @@ extract_into_parent_list(clickhouse_functions_sources dbms_sources
     multiMatchAny.cpp
     checkHyperscanRegexp.cpp
     array/has.cpp
+    equals.cpp
+    notEquals.cpp
     CastOverloadResolver.cpp
 )
 extract_into_parent_list(clickhouse_functions_headers dbms_headers

src/Functions/equals.cpp

@@ -13,6 +13,11 @@ REGISTER_FUNCTION(Equals)
     factory.registerFunction<FunctionEquals>();
 }
 
+FunctionOverloadResolverPtr createInternalFunctionEqualOverloadResolver(bool decimal_check_overflow)
+{
+    return std::make_unique<FunctionToOverloadResolverAdaptor>(std::make_shared<FunctionEquals>(decimal_check_overflow));
+}
+
 template <>
 ColumnPtr FunctionComparison<EqualsOp, NameEquals>::executeTupleImpl(
     const ColumnsWithTypeAndName & x, const ColumnsWithTypeAndName & y, size_t tuple_size, size_t input_rows_count) const

src/Functions/equals.h

@@ -0,0 +1,11 @@
+#pragma once
+#include <memory>
+
+namespace DB
+{
+
+class IFunctionOverloadResolver;
+using FunctionOverloadResolverPtr = std::shared_ptr<IFunctionOverloadResolver>;
+
+FunctionOverloadResolverPtr createInternalFunctionEqualOverloadResolver(bool decimal_check_overflow);
+}

src/Functions/notEquals.cpp

@@ -12,6 +12,11 @@ REGISTER_FUNCTION(NotEquals)
     factory.registerFunction<FunctionNotEquals>();
 }
 
+FunctionOverloadResolverPtr createInternalFunctionNotEqualOverloadResolver(bool decimal_check_overflow)
+{
+    return std::make_unique<FunctionToOverloadResolverAdaptor>(std::make_shared<FunctionNotEquals>(decimal_check_overflow));
+}
+
 template <>
 ColumnPtr FunctionComparison<NotEqualsOp, NameNotEquals>::executeTupleImpl(
     const ColumnsWithTypeAndName & x, const ColumnsWithTypeAndName & y, size_t tuple_size, size_t input_rows_count) const

src/Functions/notEquals.h

@@ -0,0 +1,11 @@
+#pragma once
+#include <memory>
+
+namespace DB
+{
+
+class IFunctionOverloadResolver;
+using FunctionOverloadResolverPtr = std::shared_ptr<IFunctionOverloadResolver>;
+
+FunctionOverloadResolverPtr createInternalFunctionNotEqualOverloadResolver(bool decimal_check_overflow);
+}

src/Storages/tests/gtest_transform_query_for_external_database.cpp

@@ -306,7 +306,8 @@ TEST(TransformQueryForExternalDatabase, Aliases)
 
     check(state, 1, {"field"},
           "SELECT field AS value, field AS display FROM table WHERE field NOT IN ('') AND display LIKE '%test%'",
-          R"(SELECT "field" FROM "test"."table" WHERE ("field" NOT IN ('')) AND ("field" LIKE '%test%'))");
+          R"(SELECT "field" FROM "test"."table" WHERE ("field" NOT IN ('')) AND ("field" LIKE '%test%'))",
+          R"(SELECT "field" FROM "test"."table" WHERE ("field" != '') AND ("field" LIKE '%test%'))");
 }
 
 TEST(TransformQueryForExternalDatabase, ForeignColumnInWhere)
@@ -408,5 +409,6 @@ TEST(TransformQueryForExternalDatabase, Analyzer)
 
     check(state, 1, {"column", "apply_id", "apply_type", "apply_status", "create_time", "field", "value", "a", "b", "foo"},
         "SELECT * FROM table WHERE (column) IN (1)",
-        R"(SELECT "column", "apply_id", "apply_type", "apply_status", "create_time", "field", "value", "a", "b", "foo" FROM "test"."table" WHERE "column" IN (1))");
+        R"(SELECT "column", "apply_id", "apply_type", "apply_status", "create_time", "field", "value", "a", "b", "foo" FROM "test"."table" WHERE "column" IN (1))",
+        R"(SELECT "column", "apply_id", "apply_type", "apply_status", "create_time", "field", "value", "a", "b", "foo" FROM "test"."table" WHERE "column" = 1)");
 }

tests/performance/function_in.xml

@@ -0,0 +1,28 @@
+<test>
+    <settings>
+        <max_insert_threads>8</max_insert_threads>
+        <max_threads>1</max_threads>
+    </settings>
+
+    <create_query>
+        CREATE TABLE t_nullable
+        (
+        key_string1 Nullable(String),
+        key_string2 Nullable(String),
+        key_string3 Nullable(String),
+        key_int64_1 Nullable(Int64),
+        key_int64_2 Nullable(Int64),
+        key_int64_3 Nullable(Int64),
+        key_int64_4 Nullable(Int64),
+        key_int64_5 Nullable(Int64),
+        m1 Int64,
+        m2 Int64
+        )
+        ENGINE = Memory
+    </create_query>
+    <fill_query>insert into t_nullable select ['aaaaaa','bbaaaa','ccaaaa','ddaaaa'][number % 101 + 1], ['aa','bb','cc','dd'][number % 100 + 1], ['aa','bb','cc','dd'][number % 102 + 1], number%10+1, number%10+2, number%10+3, number%10+4,number%10+5, number%6000+1, number%5000+2 from numbers_mt(30000000)</fill_query>
+    <query>select * from t_nullable where key_string1 in ('aaaaaa') format Null SETTINGS allow_experimental_analyzer=1</query>
+    <query>select * from t_nullable where key_string2 in ('3') format Null SETTINGS allow_experimental_analyzer=1</query>
+    <drop_query>drop table if exists t_nullable</drop_query>
+
+</test>