diff --git a/include/tao/pq/result.hpp b/include/tao/pq/result.hpp
index 0485609..7adec8b 100644
--- a/include/tao/pq/result.hpp
+++ b/include/tao/pq/result.hpp
@@ -5,6 +5,7 @@
 #ifndef TAO_PQ_RESULT_HPP
 #define TAO_PQ_RESULT_HPP
 
+#include <cassert>
 #include <cstddef>
 #include <cstdint>
 #include <format>
@@ -46,13 +47,6 @@ namespace tao::pq
       const std::size_t m_columns;
       const std::size_t m_rows;
 
-      void check_has_result_set() const
-      {
-         if( m_columns == 0 ) {
-            throw std::logic_error( "statement does not yield a result set" );
-         }
-      }
-
       void check_row( const std::size_t row ) const;
 
       explicit result( PGresult* pgresult );
@@ -69,13 +63,13 @@ namespace tao::pq
       [[nodiscard]] auto name( const std::size_t column ) const -> std::string;
       [[nodiscard]] auto index( const internal::zsv in_name ) const -> std::size_t;
 
-      [[nodiscard]] auto size() const -> std::size_t
+      [[nodiscard]] auto size() const noexcept -> std::size_t
       {
-         check_has_result_set();
+         assert( m_columns != 0 );
          return m_rows;
       }
 
-      [[nodiscard]] auto empty() const -> bool
+      [[nodiscard]] auto empty() const noexcept -> bool
       {
          return size() == 0;
       }
@@ -196,15 +190,15 @@ namespace tao::pq
       };
 
    public:
-      [[nodiscard]] auto begin() const -> const_iterator;
-      [[nodiscard]] auto end() const -> const_iterator;
+      [[nodiscard]] auto begin() const noexcept -> const_iterator;
+      [[nodiscard]] auto end() const noexcept -> const_iterator;
 
-      [[nodiscard]] auto cbegin() const
+      [[nodiscard]] auto cbegin() const noexcept
       {
          return begin();
       }
 
-      [[nodiscard]] auto cend() const
+      [[nodiscard]] auto cend() const noexcept
       {
          return end();
       }
@@ -265,7 +259,7 @@ namespace tao::pq
          requires result_type< typename T::value_type >
       [[nodiscard]] auto as_container() const -> T
       {
-         check_has_result_set();
+         assert( m_columns != 0 );
          T nrv;
          if constexpr( requires { nrv.reserve( size() ); } ) {
             nrv.reserve( size() );
diff --git a/src/lib/pq/result.cpp b/src/lib/pq/result.cpp
index 1a92a96..91fcb26 100644
--- a/src/lib/pq/result.cpp
+++ b/src/lib/pq/result.cpp
@@ -21,7 +21,7 @@ namespace tao::pq
 {
    void result::check_row( const std::size_t row ) const
    {
-      check_has_result_set();
+      assert( m_columns != 0 );
       if( !( row < m_rows ) ) {
          if( m_rows == 0 ) {
             throw std::out_of_range( std::format( "row {} out of range, result is empty", row ) );
@@ -81,22 +81,22 @@ namespace tao::pq
 
    auto result::index( const internal::zsv in_name ) const -> std::size_t
    {
+      assert( m_columns != 0 );
       const int column = PQfnumber( m_pgresult.get(), in_name );
       if( column < 0 ) {
          assert( column == -1 );
-         check_has_result_set();
          throw std::out_of_range( std::format( "column '{}' not found", in_name.value ) );
       }
       return column;
    }
 
-   auto result::begin() const -> result::const_iterator
+   auto result::begin() const noexcept -> result::const_iterator
    {
-      check_has_result_set();
+      assert( m_columns != 0 );
       return const_iterator( row( *this, 0, 0, m_columns ) );
    }
 
-   auto result::end() const -> result::const_iterator
+   auto result::end() const noexcept -> result::const_iterator
    {
       return const_iterator( row( *this, size(), 0, m_columns ) );
    }
diff --git a/src/test/pq/connection.cpp b/src/test/pq/connection.cpp
index 2fe3b1a..3ab08b3 100644
--- a/src/test/pq/connection.cpp
+++ b/src/test/pq/connection.cpp
@@ -71,7 +71,7 @@ namespace
       TEST_THROWS( connection->execute( "drop_table", 42 ) );
 
       // a statement which is not a query does not return "affected rows"
-      TEST_THROWS( connection->execute( "drop_table" ).rows_affected() );
+      TEST_ASSERT( connection->execute( "drop_table" ).columns() == 0 );
 
       // deallocate a prepared statement
       connection->deallocate( "drop_table" );
@@ -115,7 +115,7 @@ namespace
       connection->execute( "CREATE TABLE tao_connection_test ( a INTEGER PRIMARY KEY, b INTEGER )" );
 
       // a DELETE statement does not yield a result set
-      TEST_THROWS( connection->execute( "DELETE FROM tao_connection_test" ).empty() );
+      TEST_ASSERT( connection->execute( "DELETE FROM tao_connection_test" ).columns() == 0 );
 
       // out of range access throws
       TEST_THROWS( connection->execute( "SELECT * FROM tao_connection_test" ).at( 0 ) );