diff --git a/include/sqlpp11/boolean.h b/include/sqlpp11/boolean.h
index a1a36947..85658aeb 100644
--- a/include/sqlpp11/boolean.h
+++ b/include/sqlpp11/boolean.h
@@ -95,13 +95,20 @@ namespace sqlpp
 
 				bool _is_trivial() const { return value() == false; }
 
-				bool is_null() const { return _is_null; }
+				bool is_null() const
+			 	{ 
+					if (not _is_valid)
+						throw exception("accessing is_null in non-existing row");
+					return _is_null; 
+				}
+
 				bool value() const
 				{
 					if (not _is_valid)
 						throw exception("accessing value in non-existing row");
 					return _value;
 				}
+
 				operator bool() const { return value(); }
 
 			private:
diff --git a/include/sqlpp11/numeric.h b/include/sqlpp11/numeric.h
index cfbed5d3..1c9af404 100644
--- a/include/sqlpp11/numeric.h
+++ b/include/sqlpp11/numeric.h
@@ -72,13 +72,20 @@ namespace sqlpp
 
 				bool _is_trivial() const { return value() == 0; }
 
-				bool is_null() const { return _is_null; }
+				bool is_null() const
+			 	{ 
+					if (not _is_valid)
+						throw exception("accessing is_null in non-existing row");
+					return _is_null; 
+				}
+
 				int64_t value() const
 				{
 					if (not _is_valid)
 						throw exception("accessing value in non-existing row");
 					return _value;
 				}
+
 				operator int64_t() const { return value(); }
 
 			private:
diff --git a/include/sqlpp11/text.h b/include/sqlpp11/text.h
index 6eeb64ab..0a906486 100644
--- a/include/sqlpp11/text.h
+++ b/include/sqlpp11/text.h
@@ -86,13 +86,20 @@ namespace sqlpp
 				bool operator==(const std::string& rhs) const { return value() == rhs; }
 				bool operator!=(const std::string& rhs) const { return not operator==(rhs); }
 
-				bool is_null() const { return _is_null; }
+				bool is_null() const
+			 	{ 
+					if (not _is_valid)
+						throw exception("accessing is_null in non-existing row");
+					return _is_null; 
+				}
+
 				std::string value() const
 				{
 					if (not _is_valid)
 						throw exception("accessing value in non-existing row");
 					return _value;
 				}
+
 				operator std::string() const { return value(); }
 
 			private: