diff --git a/lib/click_house/type/boolean_type.rb b/lib/click_house/type/boolean_type.rb
index e4d76e7..e833078 100644
--- a/lib/click_house/type/boolean_type.rb
+++ b/lib/click_house/type/boolean_type.rb
@@ -5,18 +5,14 @@ module Type
     class BooleanType < BaseType
       TRUE_VALUE = 1
       FALSE_VALUE = 0
+      TRUE_VALUES = Set[1, '1', true].freeze
 
       def cast(value)
-        case value
-        when TrueClass, FalseClass
-          value
-        else
-          value.to_i == TRUE_VALUE
-        end
+        TRUE_VALUES.include?(value)
       end
 
       def serialize(value)
-        value ? TRUE_VALUE : FALSE_VALUE
+        TRUE_VALUES.include?(value) ? TRUE_VALUE : FALSE_VALUE
       end
     end
   end
diff --git a/spec/click_house/integration/boolean_type_spec.rb b/spec/click_house/integration/boolean_type_spec.rb
index f35e79f..8294db8 100644
--- a/spec/click_house/integration/boolean_type_spec.rb
+++ b/spec/click_house/integration/boolean_type_spec.rb
@@ -35,7 +35,7 @@
       expect(got.fetch('a')).to be_a(TrueClass)
       expect(got.fetch('b')).to be_a(FalseClass)
       expect(got.fetch('c')).to be_a(TrueClass)
-      expect(got.fetch('b')).to be_a(FalseClass)
+      expect(got.fetch('d')).to be_a(FalseClass)
       expect(got.fetch('e')).to be_a(NilClass)
     end
   end
@@ -58,7 +58,7 @@
       expect(got.fetch('a')).to be_a(TrueClass)
       expect(got.fetch('b')).to be_a(FalseClass)
       expect(got.fetch('c')).to be_a(TrueClass)
-      expect(got.fetch('b')).to be_a(FalseClass)
+      expect(got.fetch('d')).to be_a(FalseClass)
       expect(got.fetch('e')).to be_a(NilClass)
     end
   end