diff --git a/include/sqlpp11/data_types/boolean/result_field.h b/include/sqlpp11/data_types/boolean/result_field.h
index 404ecd78..4041585a 100644
--- a/include/sqlpp11/data_types/boolean/result_field.h
+++ b/include/sqlpp11/data_types/boolean/result_field.h
@@ -28,10 +28,10 @@
 #define SQLPP_BOOLEAN_RESULT_FIELD_H
 
 #include <sqlpp11/basic_expression_operators.h>
-#include <sqlpp11/result_field_methods.h>
-#include <sqlpp11/type_traits.h>
 #include <sqlpp11/exception.h>
 #include <sqlpp11/result_field.h>
+#include <sqlpp11/result_field_methods.h>
+#include <sqlpp11/type_traits.h>
 #include <sqlpp11/data_types/boolean/data_type.h>
 
 namespace sqlpp
diff --git a/include/sqlpp11/data_types/boolean/serialize.h b/include/sqlpp11/data_types/boolean/serialize.h
index 85bfc980..093fc972 100644
--- a/include/sqlpp11/data_types/boolean/serialize.h
+++ b/include/sqlpp11/data_types/boolean/serialize.h
@@ -27,7 +27,7 @@
 #ifndef SQLPP_BOOLEAN_SERIALIZE_H
 #define SQLPP_BOOLEAN_SERIALIZE_H
 
-#include <sqlpp11/data_types/boolean/result_field.h>
+#include <sqlpp11/result_field.h>
 #include <sqlpp11/data_types/boolean/operand.h>
 #include <ostream>
 
diff --git a/include/sqlpp11/data_types/integral.h b/include/sqlpp11/data_types/integral.h
index 39c2ae4b..c224f1c0 100644
--- a/include/sqlpp11/data_types/integral.h
+++ b/include/sqlpp11/data_types/integral.h
@@ -27,301 +27,13 @@
 #ifndef SQLPP_INTEGRAL_H
 #define SQLPP_INTEGRAL_H
 
-#include <cstdlib>
-#include <sqlpp11/basic_expression_operators.h>
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/exception.h>
-#include <sqlpp11/value_type.h>
-#include <sqlpp11/assignment.h>
-#include <sqlpp11/result_field.h>
+#include <sqlpp11/data_types/integral/data_type.h>
+#include <sqlpp11/data_types/integral/expression_operators.h>
+#include <sqlpp11/data_types/integral/column_operators.h>
+#include <sqlpp11/data_types/integral/parameter_type.h>
+#include <sqlpp11/data_types/integral/result_field.h>
+#include <sqlpp11/data_types/integral/operand.h>
+#include <sqlpp11/data_types/integral/wrap_operand.h>
+#include <sqlpp11/data_types/integral/serialize.h>
 
-namespace sqlpp
-{
-  // integral value type
-  struct integral
-  {
-    using _traits = make_traits<integral, tag::is_value_type>;
-    using _tag = tag::is_integral;
-    using _cpp_value_type = int64_t;
-
-    template <typename T>
-    using _is_valid_operand = is_numeric_t<T>;
-  };
-
-  // integral parameter value
-  template <>
-  struct parameter_value_t<integral>
-  {
-    using _value_type = integral;
-    using _cpp_value_type = typename _value_type::_cpp_value_type;
-
-    parameter_value_t() : _value(0), _is_null(true)
-    {
-    }
-
-    explicit parameter_value_t(const _cpp_value_type& val) : _value(val), _is_null(false)
-    {
-    }
-
-    parameter_value_t& operator=(const _cpp_value_type& val)
-    {
-      _value = val;
-      _is_null = false;
-      return *this;
-    }
-
-    parameter_value_t& operator=(const tvin_t<wrap_operand_t<_cpp_value_type>>& t)
-    {
-      if (t._is_trivial())
-      {
-        _value = 0;
-        _is_null = true;
-      }
-      else
-      {
-        _value = t._value._t;
-        _is_null = false;
-      }
-      return *this;
-    }
-
-    void set_null()
-    {
-      _value = 0;
-      _is_null = true;
-    }
-
-    bool is_null() const
-    {
-      return _is_null;
-    }
-
-    const _cpp_value_type& value() const
-    {
-      return _value;
-    }
-
-    operator _cpp_value_type() const
-    {
-      return _value;
-    }
-
-    template <typename Target>
-    void _bind(Target& target, size_t index) const
-    {
-      target._bind_integral_parameter(index, &_value, _is_null);
-    }
-
-  private:
-    _cpp_value_type _value;
-    bool _is_null;
-  };
-
-  // integral expression operators
-  template <typename Base>
-  struct expression_operators<Base, integral> : public basic_expression_operators<Base, integral>
-  {
-    template <typename T>
-    using _is_valid_operand = is_valid_operand<integral, T>;
-
-    template <typename T>
-    plus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator+(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    template <typename T>
-    minus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator-(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    template <typename T>
-    multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>> operator*(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    template <typename T>
-    divides_t<Base, wrap_operand_t<T>> operator/(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    template <typename T>
-    modulus_t<Base, wrap_operand_t<T>> operator%(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    unary_plus_t<integral, Base> operator+() const
-    {
-      return {*static_cast<const Base*>(this)};
-    }
-
-    unary_minus_t<integral, Base> operator-() const
-    {
-      return {*static_cast<const Base*>(this)};
-    }
-
-    template <typename T>
-    bitwise_and_t<Base, value_type_t<T>, wrap_operand_t<T>> operator&(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-
-    template <typename T>
-    bitwise_or_t<Base, value_type_t<T>, wrap_operand_t<T>> operator|(T t) const
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
-
-      return {*static_cast<const Base*>(this), {t}};
-    }
-  };
-
-  // integral column operators
-  template <typename Base>
-  struct column_operators<Base, integral>
-  {
-    template <typename T>
-    using _is_valid_operand = is_valid_operand<integral, T>;
-
-    template <typename T>
-    auto operator+=(T t) const -> assignment_t<Base, plus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
-
-      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
-    }
-
-    template <typename T>
-    auto operator-=(T t) const -> assignment_t<Base, minus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
-
-      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
-    }
-
-    template <typename T>
-    auto operator/=(T t) const -> assignment_t<Base, divides_t<Base, wrap_operand_t<T>>>
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
-
-      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
-    }
-
-    template <typename T>
-    auto operator*=(T t) const -> assignment_t<Base, multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>>>
-    {
-      using rhs = wrap_operand_t<T>;
-      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
-
-      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
-    }
-  };
-
-  // integral result field
-  template <typename Db, typename FieldSpec>
-  struct result_field_t<integral, Db, FieldSpec>
-      : public result_field_methods_t<result_field_t<integral, Db, FieldSpec>>
-  {
-    static_assert(std::is_same<value_type_of<FieldSpec>, integral>::value, "field type mismatch");
-    using _cpp_value_type = typename integral::_cpp_value_type;
-
-    result_field_t() : _is_valid(false), _is_null(true), _value(0)
-    {
-    }
-
-    void _invalidate()
-    {
-      _is_valid = false;
-      _is_null = true;
-      _value = 0;
-    }
-
-    void _validate()
-    {
-      _is_valid = true;
-    }
-
-    bool is_null() const
-    {
-      if (not _is_valid)
-        throw exception("accessing is_null in non-existing row");
-      return _is_null;
-    }
-
-    bool _is_trivial() const
-    {
-      if (not _is_valid)
-        throw exception("accessing is_null in non-existing row");
-
-      return value() == 0;
-    }
-
-    _cpp_value_type value() const
-    {
-      if (not _is_valid)
-        throw exception("accessing value in non-existing row");
-
-      if (_is_null)
-      {
-        if (enforce_null_result_treatment_t<Db>::value and not null_is_trivial_value_t<FieldSpec>::value)
-        {
-          throw exception("accessing value of NULL field");
-        }
-        else
-        {
-          return 0;
-        }
-      }
-      return _value;
-    }
-
-    template <typename Target>
-    void _bind(Target& target, size_t i)
-    {
-      target._bind_integral_result(i, &_value, &_is_null);
-    }
-
-  private:
-    bool _is_valid;
-    bool _is_null;
-    _cpp_value_type _value;
-  };
-
-  // ostream operator for integral result field
-  template <typename Db, typename FieldSpec>
-  inline std::ostream& operator<<(std::ostream& os, const result_field_t<integral, Db, FieldSpec>& e)
-  {
-    return serialize(e, os);
-  }
-
-  using tinyint = integral;
-  using smallint = integral;
-  using integer = integral;
-  using bigint = integral;
-}
 #endif
diff --git a/include/sqlpp11/data_types/integral/column_operators.h b/include/sqlpp11/data_types/integral/column_operators.h
new file mode 100644
index 00000000..72f30fd2
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/column_operators.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_COLUMN_OPERATORS_H
+#define SQLPP_INTEGRAL_COLUMN_OPERATORS_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/data_types/integral/data_type.h>
+#include <sqlpp11/data_types/column_operators.h>
+
+namespace sqlpp
+{
+  template <typename Base>
+  struct column_operators<Base, integral>
+  {
+    template <typename T>
+    using _is_valid_operand = is_valid_operand<integral, T>;
+
+    template <typename T>
+    auto operator+=(T t) const -> assignment_t<Base, plus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+
+      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
+    }
+
+    template <typename T>
+    auto operator-=(T t) const -> assignment_t<Base, minus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+
+      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
+    }
+
+    template <typename T>
+    auto operator/=(T t) const -> assignment_t<Base, divides_t<Base, wrap_operand_t<T>>>
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+
+      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
+    }
+
+    template <typename T>
+    auto operator*=(T t) const -> assignment_t<Base, multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+
+      return {*static_cast<const Base*>(this), {{*static_cast<const Base*>(this), rhs{t}}}};
+    }
+  };
+}
+
+#endif
diff --git a/include/sqlpp11/data_types/integral/data_type.h b/include/sqlpp11/data_types/integral/data_type.h
new file mode 100644
index 00000000..f029d5a9
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/data_type.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_DATA_TYPE_H
+#define SQLPP_INTEGRAL_DATA_TYPE_H
+
+#include <cstdlib>
+#include <sqlpp11/basic_expression_operators.h>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/exception.h>
+#include <sqlpp11/value_type.h>
+#include <sqlpp11/assignment.h>
+#include <sqlpp11/result_field.h>
+
+namespace sqlpp
+{
+  struct integral
+  {
+    using _traits = make_traits<integral, tag::is_value_type>;
+    using _tag = tag::is_integral;
+    using _cpp_value_type = int64_t;
+
+    template <typename T>
+    using _is_valid_operand = is_numeric_t<T>;
+  };
+
+  using tinyint = integral;
+  using smallint = integral;
+  using integer = integral;
+  using bigint = integral;
+}
+#endif
diff --git a/include/sqlpp11/data_types/integral/expression_operators.h b/include/sqlpp11/data_types/integral/expression_operators.h
new file mode 100644
index 00000000..da18e0a8
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/expression_operators.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_EXPRESSION_OPERATORS_H
+#define SQLPP_INTEGRAL_EXPRESSION_OPERATORS_H
+
+#include <sqlpp11/basic_expression_operators.h>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/data_types/integral/data_type.h>
+#include <sqlpp11/assignment.h>
+
+namespace sqlpp
+{
+  template <typename Base>
+  struct expression_operators<Base, integral> : public basic_expression_operators<Base, integral>
+  {
+    template <typename T>
+    using _is_valid_operand = is_valid_operand<integral, T>;
+
+    template <typename T>
+    plus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator+(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    template <typename T>
+    minus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator-(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    template <typename T>
+    multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>> operator*(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    template <typename T>
+    divides_t<Base, wrap_operand_t<T>> operator/(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    template <typename T>
+    modulus_t<Base, wrap_operand_t<T>> operator%(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    unary_plus_t<integral, Base> operator+() const
+    {
+      return {*static_cast<const Base*>(this)};
+    }
+
+    unary_minus_t<integral, Base> operator-() const
+    {
+      return {*static_cast<const Base*>(this)};
+    }
+
+    template <typename T>
+    bitwise_and_t<Base, value_type_t<T>, wrap_operand_t<T>> operator&(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+
+    template <typename T>
+    bitwise_or_t<Base, value_type_t<T>, wrap_operand_t<T>> operator|(T t) const
+    {
+      using rhs = wrap_operand_t<T>;
+      static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
+
+      return {*static_cast<const Base*>(this), {t}};
+    }
+  };
+}
+#endif
diff --git a/include/sqlpp11/data_types/integral/operand.h b/include/sqlpp11/data_types/integral/operand.h
new file mode 100644
index 00000000..181087ea
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/operand.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_OPERAND_H
+#define SQLPP_INTEGRAL_OPERAND_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/alias_operators.h>
+
+namespace sqlpp
+{
+  struct integral;
+
+  struct integral_operand : public alias_operators<integral_operand>
+  {
+    using _traits = make_traits<integral, tag::is_expression, tag::is_wrapped_value>;
+    using _nodes = detail::type_vector<>;
+    using _is_aggregate_expression = std::true_type;
+
+    using _value_t = int64_t;
+
+    integral_operand() : _t{}
+    {
+    }
+
+    integral_operand(_value_t t) : _t(t)
+    {
+    }
+
+    integral_operand(const integral_operand&) = default;
+    integral_operand(integral_operand&&) = default;
+    integral_operand& operator=(const integral_operand&) = default;
+    integral_operand& operator=(integral_operand&&) = default;
+    ~integral_operand() = default;
+
+    bool _is_trivial() const
+    {
+      return _t == 0;
+    }
+
+    _value_t _t;
+  };
+}
+
+#endif
diff --git a/include/sqlpp11/data_types/integral/parameter_type.h b/include/sqlpp11/data_types/integral/parameter_type.h
new file mode 100644
index 00000000..3d256d45
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/parameter_type.h
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_PARAMETER_TYPE_H
+#define SQLPP_INTEGRAL_PARAMETER_TYPE_H
+
+#include <sqlpp11/data_types/parameter_value.h>
+#include <sqlpp11/data_types/integral/data_type.h>
+#include <sqlpp11/data_types/integral/wrap_operand.h>
+#include <sqlpp11/data_types/integral/operand.h>
+#include <sqlpp11/tvin.h>
+
+namespace sqlpp
+{
+  template <>
+  struct parameter_value_t<integral>
+  {
+    using _value_type = integral;
+    using _cpp_value_type = typename _value_type::_cpp_value_type;
+
+    parameter_value_t() : _value(0), _is_null(true)
+    {
+    }
+
+    explicit parameter_value_t(const _cpp_value_type& val) : _value(val), _is_null(false)
+    {
+    }
+
+    parameter_value_t& operator=(const _cpp_value_type& val)
+    {
+      _value = val;
+      _is_null = false;
+      return *this;
+    }
+
+    parameter_value_t& operator=(const tvin_t<wrap_operand_t<_cpp_value_type>>& t)
+    {
+      if (t._is_trivial())
+      {
+        _value = 0;
+        _is_null = true;
+      }
+      else
+      {
+        _value = t._value._t;
+        _is_null = false;
+      }
+      return *this;
+    }
+
+    void set_null()
+    {
+      _value = 0;
+      _is_null = true;
+    }
+
+    bool is_null() const
+    {
+      return _is_null;
+    }
+
+    const _cpp_value_type& value() const
+    {
+      return _value;
+    }
+
+    operator _cpp_value_type() const
+    {
+      return _value;
+    }
+
+    template <typename Target>
+    void _bind(Target& target, size_t index) const
+    {
+      target._bind_integral_parameter(index, &_value, _is_null);
+    }
+
+  private:
+    _cpp_value_type _value;
+    bool _is_null;
+  };
+}
+#endif
diff --git a/include/sqlpp11/data_types/integral/result_field.h b/include/sqlpp11/data_types/integral/result_field.h
new file mode 100644
index 00000000..f36eb2da
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/result_field.h
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_RESULT_FIELD_H
+#define SQLPP_INTEGRAL_RESULT_FIELD_H
+
+#include <sqlpp11/basic_expression_operators.h>
+#include <sqlpp11/exception.h>
+#include <sqlpp11/result_field.h>
+#include <sqlpp11/result_field_methods.h>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/data_types/integral/data_type.h>
+
+namespace sqlpp
+{
+  template <typename Db, typename FieldSpec>
+  struct result_field_t<integral, Db, FieldSpec>
+      : public result_field_methods_t<result_field_t<integral, Db, FieldSpec>>
+  {
+    static_assert(std::is_same<value_type_of<FieldSpec>, integral>::value, "field type mismatch");
+    using _cpp_value_type = typename integral::_cpp_value_type;
+
+    result_field_t() : _is_valid(false), _is_null(true), _value(0)
+    {
+    }
+
+    void _invalidate()
+    {
+      _is_valid = false;
+      _is_null = true;
+      _value = 0;
+    }
+
+    void _validate()
+    {
+      _is_valid = true;
+    }
+
+    bool is_null() const
+    {
+      if (not _is_valid)
+        throw exception("accessing is_null in non-existing row");
+      return _is_null;
+    }
+
+    bool _is_trivial() const
+    {
+      if (not _is_valid)
+        throw exception("accessing is_null in non-existing row");
+
+      return value() == 0;
+    }
+
+    _cpp_value_type value() const
+    {
+      if (not _is_valid)
+        throw exception("accessing value in non-existing row");
+
+      if (_is_null)
+      {
+        if (enforce_null_result_treatment_t<Db>::value and not null_is_trivial_value_t<FieldSpec>::value)
+        {
+          throw exception("accessing value of NULL field");
+        }
+        else
+        {
+          return 0;
+        }
+      }
+      return _value;
+    }
+
+    template <typename Target>
+    void _bind(Target& target, size_t i)
+    {
+      target._bind_integral_result(i, &_value, &_is_null);
+    }
+
+  private:
+    bool _is_valid;
+    bool _is_null;
+    _cpp_value_type _value;
+  };
+}
+#endif
diff --git a/include/sqlpp11/data_types/integral/serialize.h b/include/sqlpp11/data_types/integral/serialize.h
new file mode 100644
index 00000000..857713b1
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/serialize.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_SERIALIZE_H
+#define SQLPP_INTEGRAL_SERIALIZE_H
+
+#include <sqlpp11/result_field.h>
+#include <sqlpp11/data_types/integral/operand.h>
+#include <ostream>
+
+namespace sqlpp
+{
+  template <typename Context>
+  struct serializer_t<Context, integral_operand>
+  {
+    using _serialize_check = consistent_t;
+    using Operand = integral_operand;
+
+    static Context& _(const Operand& t, Context& context)
+    {
+      context << t._t;
+      return context;
+    }
+  };
+
+  template <typename Db, typename FieldSpec>
+  inline std::ostream& operator<<(std::ostream& os, const result_field_t<integral, Db, FieldSpec>& e)
+  {
+    return serialize(e, os);
+  }
+}
+#endif
diff --git a/include/sqlpp11/data_types/integral/wrap_operand.h b/include/sqlpp11/data_types/integral/wrap_operand.h
new file mode 100644
index 00000000..9c658bb4
--- /dev/null
+++ b/include/sqlpp11/data_types/integral/wrap_operand.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTEGRAL_WRAP_OPERAND_H
+#define SQLPP_INTEGRAL_WRAP_OPERAND_H
+
+#include <utility>
+#include <sqlpp11/wrap_operand.h>
+
+namespace sqlpp
+{
+  struct integral_operand;
+
+  template <typename T>
+  struct wrap_operand<T, typename std::enable_if<std::is_integral<T>::value>::type>
+  {
+    using type = integral_operand;
+  };
+}
+#endif
diff --git a/include/sqlpp11/wrap_operand.h b/include/sqlpp11/wrap_operand.h
index 9cc980b9..dfd4b73e 100644
--- a/include/sqlpp11/wrap_operand.h
+++ b/include/sqlpp11/wrap_operand.h
@@ -144,49 +144,6 @@ namespace sqlpp
     }
   };
 
-  struct integral_operand : public alias_operators<integral_operand>
-  {
-    using _traits = make_traits<integral, tag::is_expression, tag::is_wrapped_value>;
-    using _nodes = detail::type_vector<>;
-    using _is_aggregate_expression = std::true_type;
-
-    using _value_t = int64_t;
-
-    integral_operand() : _t{}
-    {
-    }
-
-    integral_operand(_value_t t) : _t(t)
-    {
-    }
-
-    integral_operand(const integral_operand&) = default;
-    integral_operand(integral_operand&&) = default;
-    integral_operand& operator=(const integral_operand&) = default;
-    integral_operand& operator=(integral_operand&&) = default;
-    ~integral_operand() = default;
-
-    bool _is_trivial() const
-    {
-      return _t == 0;
-    }
-
-    _value_t _t;
-  };
-
-  template <typename Context>
-  struct serializer_t<Context, integral_operand>
-  {
-    using _serialize_check = consistent_t;
-    using Operand = integral_operand;
-
-    static Context& _(const Operand& t, Context& context)
-    {
-      context << t._t;
-      return context;
-    }
-  };
-
   struct floating_point_operand : public alias_operators<floating_point_operand>
   {
     using _traits = make_traits<floating_point, tag::is_expression, tag::is_wrapped_value>;
@@ -285,12 +242,6 @@ namespace sqlpp
     using type = day_point_operand;
   };
 
-  template <typename T>
-  struct wrap_operand<T, typename std::enable_if<std::is_integral<T>::value>::type>
-  {
-    using type = integral_operand;
-  };
-
   template <typename T>
   struct wrap_operand<T, typename std::enable_if<std::is_floating_point<T>::value>::type>
   {