diff --git a/dbms/include/DB/AggregateFunctions/AggregateFunctionIf.h b/dbms/include/DB/AggregateFunctions/AggregateFunctionIf.h
index 652afa5e649..f8dcd6fef81 100644
--- a/dbms/include/DB/AggregateFunctions/AggregateFunctionIf.h
+++ b/dbms/include/DB/AggregateFunctions/AggregateFunctionIf.h
@@ -19,6 +19,7 @@ class AggregateFunctionIf : public IAggregateFunction
 private:
 	AggregateFunctionPtr nested_func_owner;
 	IAggregateFunction * nested_func;
+	int num_agruments;
 public:
 	AggregateFunctionIf(AggregateFunctionPtr nested_) : nested_func_owner(nested_), nested_func(nested_func_owner.get()) {}
 	
@@ -34,15 +35,15 @@ public:
 
 	void setArguments(const DataTypes & arguments)
 	{
-		if (arguments.size() != 2)
-			throw Exception("Aggregate function " + getName() + " requires exactly two arguments.", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
-		
-		if (!dynamic_cast<const DataTypeUInt8 *>(&*arguments[1]))
-			throw Exception("Illegal type " + arguments[1]->getName() + " of second argument for aggregate function " + getName() + ". Must be UInt8.",
+		num_agruments = arguments.size();
+
+		if (!dynamic_cast<const DataTypeUInt8 *>(&*arguments[num_agruments - 1]))
+			throw Exception("Illegal type " + arguments[num_agruments - 1]->getName() + " of second argument for aggregate function " + getName() + ". Must be UInt8.",
 				ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
 
 		DataTypes nested_arguments;
-		nested_arguments.push_back(arguments[0]);
+		for (int i = 0; i < num_agruments - 1; i ++)
+			nested_arguments.push_back(arguments[i]);
 		nested_func->setArguments(nested_arguments);
 	}
 
@@ -73,7 +74,7 @@ public:
 
 	void add(AggregateDataPtr place, const IColumn ** columns, size_t row_num) const
 	{
-		if (static_cast<const ColumnUInt8 &>(*columns[1]).getData()[row_num])
+		if (static_cast<const ColumnUInt8 &>(*columns[num_agruments - 1]).getData()[row_num])
 			nested_func->add(place, columns, row_num);
 	}
 
diff --git a/dbms/src/AggregateFunctions/AggregateFunctionFactory.cpp b/dbms/src/AggregateFunctions/AggregateFunctionFactory.cpp
index 4476c35de81..7a97d3a27a6 100644
--- a/dbms/src/AggregateFunctions/AggregateFunctionFactory.cpp
+++ b/dbms/src/AggregateFunctions/AggregateFunctionFactory.cpp
@@ -278,10 +278,9 @@ AggregateFunctionPtr AggregateFunctionFactory::get(const String & name, const Da
 	else if (recursion_level == 0 && name.size() >= 3 && name[name.size() - 2] == 'I' && name[name.size() - 1] == 'f')
 	{
 		/// Для агрегатных функций вида aggIf, где agg - имя другой агрегатной функции.
-		if (argument_types.size() != 2)
-			throw Exception("Incorrect number of arguments for aggregate function " + name, ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
-
-		AggregateFunctionPtr nested = get(String(name.data(), name.size() - 2), DataTypes(1, argument_types[0]), 1);
+		DataTypes nested_dt = argument_types;
+		nested_dt.pop_back();
+		AggregateFunctionPtr nested = get(String(name.data(), name.size() - 2), nested_dt);
 		return new AggregateFunctionIf(nested);
 	}
 	else