diff --git a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Helper.cs b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Helper.cs
index c1730a4ec..508cec065 100644
--- a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Helper.cs
+++ b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Helper.cs
@@ -598,7 +598,7 @@ public static List<ImmutableWithWritablePropertiesIdentityTable> CreateImmutable
                     ColumnBit = false,
                     ColumnDateTime = EpocDate.AddDays(index),
                     ColumnDateTime2 = DateTime.UtcNow.AddDays(index),
-                    ColumnDecimal = index+1,
+                    ColumnDecimal = index + 1,
                     ColumnFloat = index + 1,
                     ColumnInt = index + 1,
                     ColumnNVarChar = $"NVARCHAR{index}-Property"
@@ -901,6 +901,42 @@ public static List<DottedTable> CreateDottedTables(int count)
 
         #endregion
 
+        #region NonKeyedTable
+
+        /// <summary>
+        /// Creates a list of <see cref="NonKeyedTable"/> objects.
+        /// </summary>
+        /// <param name="count">The number of rows.</param>
+        /// <returns>A list of <see cref="NonKeyedTable"/> objects.</returns>
+        public static IEnumerable<NonKeyedTable> CreateNonKeyedTables(int count = 10)
+        {
+            for (var index = 0; index < count; index++)
+            {
+                yield return new NonKeyedTable
+                {
+                    ColumnDateTime2 = DateTime.UtcNow,
+                    ColumnInt = index,
+                    ColumnNVarChar = $"NVARCHAR{index}"
+                };
+            }
+        }
+
+        /// <summary>
+        /// Creates an instance of <see cref="NonKeyedTable"/> object.
+        /// </summary>
+        /// <returns>A new created instance of <see cref="NonKeyedTable"/> object.</returns>
+        public static NonKeyedTable CreateNonKeyedTable()
+        {
+            return new NonKeyedTable
+            {
+                ColumnDateTime2 = DateTime.UtcNow,
+                ColumnInt = new Random().Next(int.MinValue, int.MaxValue),
+                ColumnNVarChar = Guid.NewGuid().ToString()
+            };
+        }
+
+        #endregion
+
         #region Dynamics
 
         #region IdentityTable
@@ -983,53 +1019,6 @@ public static Tuple<List<dynamic>, IEnumerable<Field>> CreateDynamicIdentityTabl
             return new Tuple<List<dynamic>, IEnumerable<Field>>(tables, fields);
         }
 
-        /// <summary>
-        /// Creates a list of dynamic objects for [sc].[IdentityTable] without an identity.
-        /// </summary>
-        /// <param name="count">The number of rows.</param>
-        /// <returns>A list of dynamic objects.</returns>
-        public static List<dynamic> CreateDynamicIdentityTablesWithoutIdentity(int count)
-        {
-            var tables = new List<dynamic>();
-            for (var i = 0; i < count; i++)
-            {
-                var index = i + 1;
-                tables.Add(new
-                {
-                    RowGuid = Guid.NewGuid(),
-                    ColumnBit = true,
-                    ColumnDateTime = EpocDate.AddDays(index),
-                    ColumnDateTime2 = DateTime.UtcNow,
-                    ColumnDecimal = Convert.ToDecimal(index),
-                    ColumnFloat = Convert.ToDouble(index),
-                    ColumnInt = index,
-                    ColumnNVarChar = $"NVARCHAR{index}"
-                });
-            }
-            return tables;
-        }
-
-        /// <summary>
-        /// Creates a list of dynamic objects for [dbo].[NonKeyedTable] table.
-        /// </summary>
-        /// <param name="count">The number of rows.</param>
-        /// <returns>A list of dynamic objects.</returns>
-        public static List<dynamic> CreateDynamicNonKeyedTables(int count)
-        {
-            var tables = new List<dynamic>();
-            for (var i = 0; i < count; i++)
-            {
-                var index = i + 1;
-                tables.Add(new
-                {
-                    ColumnDateTime2 = DateTime.UtcNow,
-                    ColumnInt = index,
-                    ColumnNVarChar = $"NVARCHAR{index}"
-                });
-            }
-            return tables;
-        }
-
         #endregion
 
         #region NonIdentityTable
@@ -1111,6 +1100,45 @@ public static Tuple<List<dynamic>, IEnumerable<Field>> CreateDynamicNonIdentityT
 
         #endregion
 
+        #region NonKeyedTable
+
+        /// <summary>
+        /// Creates a list of dynamic objects for [dbo].[NonKeyedTable] table.
+        /// </summary>
+        /// <param name="count">The number of rows.</param>
+        /// <returns>A list of dynamic objects.</returns>
+        public static List<dynamic> CreateDynamicNonKeyedTables(int count)
+        {
+            var tables = new List<dynamic>();
+            for (var i = 0; i < count; i++)
+            {
+                var index = i + 1;
+                tables.Add(new
+                {
+                    ColumnDateTime2 = DateTime.UtcNow,
+                    ColumnInt = index,
+                    ColumnNVarChar = $"NVARCHAR{index}"
+                });
+            }
+            return tables;
+        }
+
+        /// <summary>
+        /// Creates an instance of dynamic object for [dbo].[NonKeyedTable] table.
+        /// </summary>
+        /// <returns>An instance of dynamic object.</returns>
+        public static dynamic CreateDynamicNonKeyedTable()
+        {
+            return new
+            {
+                ColumnDateTime2 = DateTime.UtcNow,
+                ColumnInt = new Random().Next(int.MinValue, int.MaxValue),
+                ColumnNVarChar = Guid.NewGuid().ToString()
+            };
+        }
+
+        #endregion
+
         #endregion
     }
 }
diff --git a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/MergeAllTest.cs b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/MergeAllTest.cs
index 7ef2b4272..804bf7d15 100644
--- a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/MergeAllTest.cs
+++ b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/MergeAllTest.cs
@@ -1514,16 +1514,16 @@ public void TestSqlConnectionMergeAllViaTableNameForNonIdentityEmptyTableWithHin
             }
         }
 
-        [TestMethod, ExpectedException(typeof(InvalidQualifiersException))]
+        [TestMethod, ExpectedException(typeof(KeyFieldNotFoundException))]
         public void ThrowExceptionOnSqlConnectionMergeAllIfTheKeyFieldIsNotPresent()
         {
             // Setup
-            var tables = Helper.CreateDynamicIdentityTablesWithoutIdentity(10);
+            var tables = Helper.CreateDynamicNonKeyedTables(10);
 
             using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
             {
                 // Act
-                connection.MergeAll(ClassMappedNameCache.Get<IdentityTable>(), tables);
+                connection.MergeAll(ClassMappedNameCache.Get<NonKeyedTable>(), tables);
             }
         }
 
@@ -2002,12 +2002,12 @@ public void TestSqlConnectionMergeAllAsyncViaTableNameForNonIdentityEmptyTableWi
         public void ThrowExceptionOnSqlConnectionMergeAllAsyncIfTheKeyFieldIsNotPresent()
         {
             // Setup
-            var tables = Helper.CreateDynamicIdentityTablesWithoutIdentity(10);
+            var tables = Helper.CreateNonKeyedTables(10);
 
             using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
             {
                 // Act
-                connection.MergeAllAsync(ClassMappedNameCache.Get<IdentityTable>(), tables).Wait();
+                connection.MergeAllAsync(ClassMappedNameCache.Get<NonKeyedTable>(), tables).Wait();
             }
         }
 
diff --git a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/QueryTest.cs b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/QueryTest.cs
index f018eea99..fccd211f9 100644
--- a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/QueryTest.cs
+++ b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/QueryTest.cs
@@ -390,6 +390,26 @@ public void TestSqlConnectionQueryViaExpression()
             }
         }
 
+        [TestMethod]
+        public void TestSqlConnectionQueryViaExpressionWitNullValue()
+        {
+            // Setup
+            var tables = Helper.CreateIdentityTables(10);
+            var last = tables.Last();
+
+            using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
+            {
+                // Act
+                connection.InsertAll(tables);
+
+                // Act
+                var result = connection.Query<IdentityTable>(c => c.ColumnNVarChar == null);
+
+                // Assert
+                Assert.AreEqual(0, result.Count());
+            }
+        }
+
         [TestMethod]
         public void TestSqlConnectionQueryViaQueryField()
         {
@@ -1545,6 +1565,26 @@ public void TestSqlConnectionQueryAsyncViaExpression()
             }
         }
 
+        [TestMethod]
+        public void TestSqlConnectionQueryAsyncViaExpressionWithNullValue()
+        {
+            // Setup
+            var tables = Helper.CreateIdentityTables(10);
+            var last = tables.Last();
+
+            using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
+            {
+                // Act
+                connection.InsertAll(tables);
+
+                // Act
+                var result = connection.QueryAsync<IdentityTable>(c => c.ColumnNVarChar == null).Result;
+
+                // Assert
+                Assert.AreEqual(0, result.Count());
+            }
+        }
+
         [TestMethod]
         public void TestSqlConnectionQueryAsyncViaQueryField()
         {
diff --git a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/UpdateTest.cs b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/UpdateTest.cs
index 978dde0b5..031426141 100644
--- a/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/UpdateTest.cs
+++ b/RepoDb.Core/RepoDb.Tests/RepoDb.IntegrationTests/Operations/UpdateTest.cs
@@ -1651,30 +1651,45 @@ public void TestSqlConnectionUpdateViaTableNameWithHints()
             }
         }
 
+        [TestMethod, ExpectedException(typeof(KeyFieldNotFoundException))]
+        public void ThrowExceptionOnSqlConnectionUpdateIfThereIsNoKeyField()
+        {
+            // Setup
+            var data = Helper.CreateNonKeyedTable();
+
+            using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
+            {
+                // Act
+                connection.Update<NonKeyedTable>(data);
+            }
+        }
+
         [TestMethod, ExpectedException(typeof(KeyFieldNotFoundException))]
         public void ThrowExceptionOnSqlConnectionUpdateViaTableNameIfThereIsNoKeyField()
         {
+            // Setup
+            var data = Helper.CreateDynamicNonKeyedTable();
+
             using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
             {
-                var data = new
-                {
-                    ColumnInt = 1,
-                    ColumnDecimal = 2
-                };
-                connection.Update(ClassMappedNameCache.Get<NonIdentityTable>(), data);
+                // Act
+                connection.Update(ClassMappedNameCache.Get<NonIdentityTable>(), (object)data);
             }
         }
 
         [TestMethod, ExpectedException(typeof(EmptyException))]
         public void ThrowExceptionOnSqlConnectionUpdateViaTableNameIfTheFieldsAreNotFound()
         {
+            // Setup
+            var data = new
+            {
+                Id = 1,
+                AnyField = 1
+            };
+
             using (var connection = new SqlConnection(Database.ConnectionStringForRepoDb))
             {
-                var data = new
-                {
-                    Id = 1,
-                    AnyField = 1
-                };
+                // Act
                 connection.Update(ClassMappedNameCache.Get<NonIdentityTable>(), data);
             }
         }
diff --git a/RepoDb.Core/RepoDb/Extensions/DbCommandExtension.cs b/RepoDb.Core/RepoDb/Extensions/DbCommandExtension.cs
index 02038e0dc..65166804a 100644
--- a/RepoDb.Core/RepoDb/Extensions/DbCommandExtension.cs
+++ b/RepoDb.Core/RepoDb/Extensions/DbCommandExtension.cs
@@ -237,10 +237,10 @@ private static void CreateParametersInternal(IDbCommand command,
                 var dbField = GetDbField(name, dbFields);
                 var value = classProperty.PropertyInfo.GetValue(param);
                 var returnType = (Type)null;
-                var dbType = (DbType?)null;
 
                 // Propertyhandler
-                var definition = InvokePropertyHandlerSetMethod(classProperty.GetPropertyHandler(), value, classProperty);
+                var propertyHandler = GetProperyHandler(classProperty, value?.GetType());
+                var definition = InvokePropertyHandlerSetMethod(propertyHandler, value, classProperty);
                 if (definition != null)
                 {
                     returnType = definition.ReturnType.GetUnderlyingType();
@@ -256,15 +256,9 @@ private static void CreateParametersInternal(IDbCommand command,
                 }
 
                 // DbType
-                if (returnType != null)
-                {
-                    dbType = clientTypeToDbTypeResolver.Resolve(returnType);
-                }
-                else
-                {
-                    dbType = classProperty.GetDbType() ??
-                        value?.GetType()?.GetDbType();
-                }
+                var dbType = (returnType != null ? clientTypeToDbTypeResolver.Resolve(returnType) : null) ??
+                    classProperty.GetDbType() ??
+                    value?.GetType()?.GetDbType();
 
                 // Add the parameter
                 command.Parameters.Add(command.CreateParameter(name, value, dbType));
@@ -308,7 +302,7 @@ private static void CreateParameters(IDbCommand command,
                 }
 
                 // Propertyhandler
-                var propertyHandler = classProperty?.GetPropertyHandler() ?? PropertyHandlerCache.Get<object>(valueType);
+                var propertyHandler = GetProperyHandler(classProperty, valueType);
                 var definition = InvokePropertyHandlerSetMethod(propertyHandler, value, classProperty);
                 if (definition != null)
                 {
@@ -325,7 +319,7 @@ private static void CreateParameters(IDbCommand command,
                 }
 
                 // DbType
-                var dbType = clientTypeToDbTypeResolver.Resolve(valueType) ??
+                var dbType = (valueType != null ? clientTypeToDbTypeResolver.Resolve(valueType) : null) ??
                     classProperty?.GetDbType() ??
                     value?.GetType()?.GetDbType();
 
@@ -430,7 +424,7 @@ private static void CreateParameters(this IDbCommand command,
 
             // PropertyHandler
             var classProperty = PropertyCache.Get(entityType, queryField.Field);
-            var propertyHandler = classProperty?.GetPropertyHandler<object>() ?? PropertyHandlerCache.Get<object>(valueType);
+            var propertyHandler = GetProperyHandler(classProperty, valueType);
             var definition = InvokePropertyHandlerSetMethod(propertyHandler, value, classProperty);
             if (definition != null)
             {
@@ -447,7 +441,7 @@ private static void CreateParameters(this IDbCommand command,
             }
 
             // DbType
-            var dbType = clientTypeToDbTypeResolver.Resolve(valueType) ??
+            var dbType = (valueType != null ? clientTypeToDbTypeResolver.Resolve(valueType) : null) ??
                 classProperty?.GetDbType() ??
                 value?.GetType()?.GetDbType();
 
@@ -481,7 +475,7 @@ private static void CreateParametersForInOperation(this IDbCommand command,
                     var valueType = value?.GetType()?.GetUnderlyingType();
 
                     // Propertyhandler
-                    var properyHandler = PropertyHandlerCache.Get<object>(valueType);
+                    var properyHandler = GetProperyHandler(null, valueType);
                     var definition = InvokePropertyHandlerSetMethod(properyHandler, value, null);
                     if (definition != null)
                     {
@@ -498,7 +492,7 @@ private static void CreateParametersForInOperation(this IDbCommand command,
                     }
 
                     // DbType
-                    var dbType = clientTypeToDbTypeResolver.Resolve(valueType);
+                    var dbType = (valueType != null ? clientTypeToDbTypeResolver.Resolve(valueType) : null);
 
                     // Create
                     command.Parameters.Add(CreateParameter(command, name, values[i], dbType));
@@ -528,10 +522,10 @@ private static void CreateParametersForBetweenOperation(this IDbCommand command,
                 var leftValue = values[0];
                 var rightValue = values[1];
                 var leftValueType = leftValue?.GetType()?.GetUnderlyingType();
-                var rightValueType = leftValue?.GetType()?.GetUnderlyingType();
+                var rightValueType = rightValue?.GetType()?.GetUnderlyingType();
 
                 // Propertyhandler (Left)
-                var leftPropertyHandler = PropertyHandlerCache.Get<object>(leftValueType);
+                var leftPropertyHandler = GetProperyHandler(null, leftValueType);
                 var leftdefinition = InvokePropertyHandlerSetMethod(leftPropertyHandler, leftValue, null);
                 if (leftdefinition != null)
                 {
@@ -540,8 +534,8 @@ private static void CreateParametersForBetweenOperation(this IDbCommand command,
                 }
 
                 // Propertyhandler (Right)
-                var rightPropertyHandler = PropertyHandlerCache.Get<object>(leftValueType);
-                var rightDefinition = InvokePropertyHandlerSetMethod(rightPropertyHandler, leftValue, null);
+                var rightPropertyHandler = GetProperyHandler(null, rightValueType);
+                var rightDefinition = InvokePropertyHandlerSetMethod(rightPropertyHandler, rightValue, null);
                 if (rightDefinition != null)
                 {
                     rightValueType = rightDefinition.ReturnType.GetUnderlyingType();
@@ -558,8 +552,8 @@ private static void CreateParametersForBetweenOperation(this IDbCommand command,
                 }
 
                 // DbType
-                var leftDbType = clientTypeToDbTypeResolver.Resolve(leftValueType);
-                var rightDbType = clientTypeToDbTypeResolver.Resolve(rightValueType);
+                var leftDbType = (leftValueType != null ? clientTypeToDbTypeResolver.Resolve(leftValueType) : null);
+                var rightDbType = (rightValueType != null ? clientTypeToDbTypeResolver.Resolve(rightValueType) : null);
 
                 // Add
                 command.Parameters.Add(
@@ -695,6 +689,23 @@ private static object AutomaticConvertGuidToString(object value)
             return value?.ToString();
         }
 
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="classProperty"></param>
+        /// <param name="targetType"></param>
+        /// <returns></returns>
+        private static object GetProperyHandler(ClassProperty classProperty,
+            Type targetType)
+        {
+            var propertyHandler = classProperty?.GetPropertyHandler();
+            if (propertyHandler == null && targetType != null)
+            {
+                propertyHandler = PropertyHandlerCache.Get<object>(targetType);
+            }
+            return propertyHandler;
+        }
+
         #endregion
     }
 }
diff --git a/RepoDb.Core/RepoDb/Extensions/DbConnectionExtension.cs b/RepoDb.Core/RepoDb/Extensions/DbConnectionExtension.cs
index 4558623f9..60265afa7 100644
--- a/RepoDb.Core/RepoDb/Extensions/DbConnectionExtension.cs
+++ b/RepoDb.Core/RepoDb/Extensions/DbConnectionExtension.cs
@@ -201,12 +201,12 @@ internal static IEnumerable<dynamic> ExecuteQueryInternal(this IDbConnection con
             {
                 using (var reader = command.ExecuteReader())
                 {
-                    var result = (IEnumerable<dynamic>)DataReader.ToEnumerable(reader, dbFields, connection.GetDbSetting()).AsList();
+                    var result = DataReader.ToEnumerable(reader, dbFields, connection.GetDbSetting()).AsList();
 
                     // Set Cache
                     if (cacheKey != null)
                     {
-                        cache?.Add(cacheKey, result, cacheItemExpiration.GetValueOrDefault(), false);
+                        cache?.Add(cacheKey, (IEnumerable<dynamic>)result, cacheItemExpiration.GetValueOrDefault(), false);
                     }
 
                     // Return
@@ -324,7 +324,7 @@ internal static async Task<IEnumerable<dynamic>> ExecuteQueryAsyncInternal(this
             {
                 using (var reader = await command.ExecuteReaderAsync(cancellationToken))
                 {
-                    var result = (await DataReader.ToEnumerableAsync(reader, dbFields, connection.GetDbSetting(), cancellationToken)).AsList();
+                    var result = await DataReader.ToEnumerableAsync(reader, dbFields, connection.GetDbSetting());
 
                     // Set Cache
                     if (cacheKey != null)
@@ -576,13 +576,12 @@ private static IEnumerable<TResult> ExecuteQueryInternalForType<TResult>(this ID
             {
                 using (var reader = command.ExecuteReader())
                 {
-                    var result = (IEnumerable<TResult>)DataReader.ToEnumerable<TResult>(reader,
-                        dbFields, connection.GetDbSetting()).AsList();
+                    var result = DataReader.ToEnumerable<TResult>(reader, dbFields, connection.GetDbSetting()).AsList();
 
                     // Set Cache
                     if (cacheKey != null)
                     {
-                        cache?.Add(cacheKey, result, cacheItemExpiration.GetValueOrDefault(), false);
+                        cache?.Add(cacheKey, (IEnumerable<TResult>)result, cacheItemExpiration.GetValueOrDefault(), false);
                     }
 
                     // Return
@@ -842,7 +841,8 @@ private static async Task<IEnumerable<TResult>> ExecuteQueryAsyncInternalForType
             {
                 using (var reader = await command.ExecuteReaderAsync(cancellationToken))
                 {
-                    var result = (await DataReader.ToEnumerableAsync<TResult>(reader, dbFields, connection.GetDbSetting(), cancellationToken)).AsList();
+                    var result = await DataReader.ToEnumerableAsync<TResult>(reader, dbFields,
+                        connection.GetDbSetting());
 
                     // Set Cache
                     if (cacheKey != null)
@@ -1692,13 +1692,27 @@ internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(IDbCon
         internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(IDbConnection connection,
             string tableName,
             IDbTransaction transaction)
-            where TEntity : class
+            where TEntity : class =>
+            GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction, typeof(TEntity));
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="connection"></param>
+        /// <param name="tableName"></param>
+        /// <param name="transaction"></param>
+        /// <param name="entityType"></param>
+        /// <returns></returns>
+        internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey(IDbConnection connection,
+            string tableName,
+            IDbTransaction transaction,
+            Type entityType)
         {
-            var property = PrimaryCache.Get<TEntity>() ?? IdentityCache.Get<TEntity>();
+            var dbFields = DbFieldCache.Get(connection, tableName, transaction);
+            var property = GetAndGuardPrimaryKeyOrIdentityKey(entityType, dbFields);
             if (property == null)
             {
-                var dbFields = DbFieldCache.Get(connection, tableName, transaction);
-                property = GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(dbFields);
+                property = GetPrimaryOrIdentityKey(entityType);
             }
             return GetAndGuardPrimaryKeyOrIdentityKey(tableName, property);
         }
@@ -1709,13 +1723,13 @@ internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(IDbCon
         /// <typeparam name="TEntity"></typeparam>
         /// <param name="connection"></param>
         /// <param name="transaction"></param>
-        /// <param name="cancellation"></param>
+        /// <param name="cancellationToken"></param>
         /// <returns></returns>
         internal static Task<ClassProperty> GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEntity>(IDbConnection connection,
             IDbTransaction transaction,
-            CancellationToken cancellation = default)
+            CancellationToken cancellationToken = default)
             where TEntity : class =>
-            GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEntity>(connection, ClassMappedNameCache.Get<TEntity>(), transaction, cancellation);
+            GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEntity>(connection, ClassMappedNameCache.Get<TEntity>(), transaction, cancellationToken);
 
         /// <summary>
         /// 
@@ -1726,17 +1740,33 @@ internal static Task<ClassProperty> GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEnt
         /// <param name="transaction"></param>
         /// <param name="cancellationToken"></param>
         /// <returns></returns>
-        internal static async Task<ClassProperty> GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEntity>(IDbConnection connection,
+        internal static Task<ClassProperty> GetAndGuardPrimaryKeyOrIdentityKeyAsync<TEntity>(IDbConnection connection,
             string tableName,
             IDbTransaction transaction,
             CancellationToken cancellationToken = default)
-            where TEntity : class
+            where TEntity : class =>
+            GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, typeof(TEntity), cancellationToken);
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="connection"></param>
+        /// <param name="tableName"></param>
+        /// <param name="transaction"></param>
+        /// <param name="entityType"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        internal static async Task<ClassProperty> GetAndGuardPrimaryKeyOrIdentityKeyAsync(IDbConnection connection,
+            string tableName,
+            IDbTransaction transaction,
+            Type entityType,
+            CancellationToken cancellationToken = default)
         {
-            var property = PrimaryCache.Get<TEntity>() ?? IdentityCache.Get<TEntity>();
+            var dbFields = await DbFieldCache.GetAsync(connection, tableName, transaction, cancellationToken);
+            var property = GetAndGuardPrimaryKeyOrIdentityKey(entityType, dbFields);
             if (property == null)
             {
-                var dbFields = await DbFieldCache.GetAsync(connection, tableName, transaction, cancellationToken);
-                property = GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(dbFields);
+                property = GetPrimaryOrIdentityKey(entityType);
             }
             return GetAndGuardPrimaryKeyOrIdentityKey(tableName, property);
         }
@@ -1760,21 +1790,48 @@ internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey(string tableNam
         /// <summary>
         /// 
         /// </summary>
-        /// <typeparam name="TEntity"></typeparam>
+        /// <param name="entityType"></param>
         /// <param name="dbFields"></param>
         /// <returns></returns>
-        internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey<TEntity>(IEnumerable<DbField> dbFields)
-            where TEntity : class
+        internal static ClassProperty GetAndGuardPrimaryKeyOrIdentityKey(Type entityType,
+            IEnumerable<DbField> dbFields)
         {
-            var dbField = dbFields?.FirstOrDefault(df => df.IsPrimary == true) ??
-                dbFields?.FirstOrDefault(df => df.IsIdentity == true);
-            if (dbField != null)
+            if (entityType == null)
+            {
+                return null;
+            }
+
+            // Properties
+            var properties = PropertyCache.Get(entityType) ?? entityType?.GetClassProperties();
+            var key = (ClassProperty)null;
+
+            // Primary
+            if (key == null)
+            {
+                var dbField = dbFields?.FirstOrDefault(df => df.IsPrimary == true);
+                key = properties?.FirstOrDefault(p =>
+                     string.Equals(p.GetMappedName(), dbField?.Name, StringComparison.OrdinalIgnoreCase)) ??
+                     PrimaryCache.Get(entityType);
+            }
+
+            // Identity
+            if (key == null)
+            {
+                var dbField = dbFields?.FirstOrDefault(df => df.IsIdentity == true);
+                key = properties?.FirstOrDefault(p =>
+                     string.Equals(p.GetMappedName(), dbField?.Name, StringComparison.OrdinalIgnoreCase)) ??
+                     PrimaryCache.Get(entityType);
+            }
+
+            // Return
+            if (key != null)
+            {
+                return key;
+            }
+            else
             {
-                var properties = PropertyCache.Get<TEntity>() ?? typeof(TEntity).GetClassProperties();
-                return properties.FirstOrDefault(p =>
-                    string.Equals(p.GetMappedName(), dbField.Name, StringComparison.OrdinalIgnoreCase));
+                throw new KeyFieldNotFoundException($"No primary key and identify found at type '{entityType.FullName}'.");
             }
-            throw new KeyFieldNotFoundException($"No primary key and identify found at type '{typeof(TEntity).Name}'.");
         }
 
         /// <summary>
@@ -1852,8 +1909,17 @@ internal static QueryGroup WhatToQueryGroup<T>(this IDbConnection connection,
             var queryGroup = WhatToQueryGroup<T>(what);
             if (queryGroup == null)
             {
-                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
-                queryGroup = WhatToQueryGroup<T>(key, what);
+                var whatType = what?.GetType();
+                if (whatType.IsClassType() || whatType.IsAnonymousType())
+                {
+                    var classProperty = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction, whatType);
+                    queryGroup = WhatToQueryGroup<T>(classProperty, what);
+                }
+                else
+                {
+                    var dbField = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+                    queryGroup = WhatToQueryGroup<T>(dbField, what);
+                }
             }
             return queryGroup;
         }
@@ -1881,8 +1947,17 @@ internal static async Task<QueryGroup> WhatToQueryGroupAsync<T>(this IDbConnecti
             var queryGroup = WhatToQueryGroup<T>(what);
             if (queryGroup == null)
             {
-                var dbField = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
-                queryGroup = WhatToQueryGroup<T>(dbField, what);
+                var whatType = what?.GetType();
+                if (whatType.IsClassType() || whatType.IsAnonymousType())
+                {
+                    var classProperty = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, whatType, cancellationToken);
+                    queryGroup = WhatToQueryGroup<T>(classProperty, what);
+                }
+                else
+                {
+                    var dbField = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+                    queryGroup = WhatToQueryGroup<T>(dbField, what);
+                }
             }
             return queryGroup;
         }
@@ -2171,10 +2246,18 @@ internal static QueryGroup ToQueryGroup(IEnumerable<QueryField> queryFields)
         #endregion
 
         /// <summary>
-        /// Throws an exception if the entities argument is null or empty.
+        /// 
         /// </summary>
-        /// <typeparam name="TEntity">The type of the result.</typeparam>
-        /// <param name="entities">The enumerable list of entity objects.</param>
+        /// <param name="entityType"></param>
+        /// <returns></returns>
+        internal static ClassProperty GetPrimaryOrIdentityKey(Type entityType) =>
+            entityType != null ? (PrimaryCache.Get(entityType) ?? IdentityCache.Get(entityType)) : null;
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <typeparam name="TEntity"></typeparam>
+        /// <param name="entities"></param>
         internal static void ThrowIfNullOrEmpty<TEntity>(IEnumerable<TEntity> entities)
             where TEntity : class
         {
diff --git a/RepoDb.Core/RepoDb/Operations/DbConnection/Merge.cs b/RepoDb.Core/RepoDb/Operations/DbConnection/Merge.cs
index f1d32574c..79a334011 100644
--- a/RepoDb.Core/RepoDb/Operations/DbConnection/Merge.cs
+++ b/RepoDb.Core/RepoDb/Operations/DbConnection/Merge.cs
@@ -1915,7 +1915,8 @@ internal static TResult MergeInternalBase<TEntity, TResult>(this IDbConnection c
             // Check the qualifiers
             if (qualifiers?.Any() != true)
             {
-                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction,
+                    entity?.GetType() ?? typeof(TEntity));
                 qualifiers = key.AsField().AsEnumerable();
             }
 
@@ -2177,7 +2178,8 @@ internal static async Task<TResult> MergeAsyncInternalBase<TEntity, TResult>(thi
             // Check the qualifiers
             if (qualifiers?.Any() != true)
             {
-                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction,
+                    entity?.GetType() ?? typeof(TEntity), cancellationToken);
                 qualifiers = key.AsField().AsEnumerable();
             }
 
diff --git a/RepoDb.Core/RepoDb/Operations/DbConnection/MergeAll.cs b/RepoDb.Core/RepoDb/Operations/DbConnection/MergeAll.cs
index 0d025bede..776b55b65 100644
--- a/RepoDb.Core/RepoDb/Operations/DbConnection/MergeAll.cs
+++ b/RepoDb.Core/RepoDb/Operations/DbConnection/MergeAll.cs
@@ -377,7 +377,8 @@ internal static int MergeAllInternal<TEntity>(this IDbConnection connection,
             // Check the qualifiers
             if (qualifiers?.Any() != true)
             {
-                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction,
+                    entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity));
                 qualifiers = key.AsField().AsEnumerable();
             }
 
@@ -800,7 +801,8 @@ internal static async Task<int> MergeAllAsyncInternal<TEntity>(this IDbConnectio
             // Check the qualifiers
             if (qualifiers?.Any() != true)
             {
-                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction,
+                    entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity), cancellationToken);
                 qualifiers = key.AsField().AsEnumerable();
             }
 
@@ -1359,7 +1361,7 @@ internal static int UpsertAllInternalBase<TEntity>(this IDbConnection connection
             where TEntity : class
         {
             // Variables needed
-            var type = entities?.First()?.GetType() ?? typeof(TEntity);
+            var type = entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity);
             var isObjectType = typeof(TEntity) == StaticType.Object;
             var dbFields = DbFieldCache.Get(connection, tableName, transaction);
             var primary = dbFields?.FirstOrDefault(dbField => dbField.IsPrimary);
@@ -1760,7 +1762,7 @@ internal static async Task<int> UpsertAllAsyncInternalBase<TEntity>(this IDbConn
             where TEntity : class
         {
             // Variables needed
-            var type = entities?.First()?.GetType() ?? typeof(TEntity);
+            var type = entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity);
             var isObjectType = typeof(TEntity) == StaticType.Object;
             var dbFields = await DbFieldCache.GetAsync(connection, tableName, transaction, cancellationToken);
             var primary = dbFields?.FirstOrDefault(dbField => dbField.IsPrimary);
diff --git a/RepoDb.Core/RepoDb/Operations/DbConnection/Update.cs b/RepoDb.Core/RepoDb/Operations/DbConnection/Update.cs
index c9d4ee67d..ad99f4769 100644
--- a/RepoDb.Core/RepoDb/Operations/DbConnection/Update.cs
+++ b/RepoDb.Core/RepoDb/Operations/DbConnection/Update.cs
@@ -45,7 +45,8 @@ public static int Update<TEntity>(this IDbConnection connection,
             IStatementBuilder statementBuilder = null)
             where TEntity : class
         {
-            var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+            var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction,
+                entity?.GetType() ?? typeof(TEntity));
             return UpdateInternal<TEntity>(connection: connection,
                 tableName: tableName,
                 entity: entity,
@@ -622,7 +623,8 @@ public static async Task<int> UpdateAsync<TEntity>(this IDbConnection connection
             CancellationToken cancellationToken = default)
             where TEntity : class
         {
-            var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+            var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction,
+                entity?.GetType() ?? typeof(TEntity), cancellationToken);
             return await UpdateAsyncInternal<TEntity>(connection: connection,
                 tableName: tableName,
                 entity: entity,
@@ -1238,7 +1240,7 @@ public static int Update(this IDbConnection connection,
             ITrace trace = null,
             IStatementBuilder statementBuilder = null)
         {
-            var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+            var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction, entity?.GetType());
             return UpdateInternal<object>(connection: connection,
                 tableName: tableName,
                 entity: entity,
@@ -1428,7 +1430,8 @@ public static async Task<int> UpdateAsync(this IDbConnection connection,
             IStatementBuilder statementBuilder = null,
             CancellationToken cancellationToken = default)
         {
-            var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+            var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction,
+                entity?.GetType(), cancellationToken);
             return await UpdateAsyncInternal<object>(connection: connection,
                 tableName: tableName,
                 entity: entity,
diff --git a/RepoDb.Core/RepoDb/Operations/DbConnection/UpdateAll.cs b/RepoDb.Core/RepoDb/Operations/DbConnection/UpdateAll.cs
index fdcba341f..fdafbf4f4 100644
--- a/RepoDb.Core/RepoDb/Operations/DbConnection/UpdateAll.cs
+++ b/RepoDb.Core/RepoDb/Operations/DbConnection/UpdateAll.cs
@@ -376,7 +376,8 @@ internal static int UpdateAllInternal<TEntity>(this IDbConnection connection,
         {
             if (qualifiers?.Any() != true)
             {
-                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction);
+                var key = GetAndGuardPrimaryKeyOrIdentityKey(connection, tableName, transaction,
+                    entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity));
                 qualifiers = key.AsField().AsEnumerable();
             }
             return UpdateAllInternalBase<TEntity>(connection: connection,
@@ -777,7 +778,8 @@ internal static async Task<int> UpdateAllAsyncInternal<TEntity>(this IDbConnecti
         {
             if (qualifiers?.Any() != true)
             {
-                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction, cancellationToken);
+                var key = await GetAndGuardPrimaryKeyOrIdentityKeyAsync(connection, tableName, transaction,
+                    entities?.FirstOrDefault()?.GetType() ?? typeof(TEntity), cancellationToken);
                 qualifiers = key.AsField().AsEnumerable();
             }
             return await UpdateAllAsyncInternalBase<TEntity>(connection: connection,
diff --git a/RepoDb.Core/RepoDb/RepoDb.csproj b/RepoDb.Core/RepoDb/RepoDb.csproj
index 926983ffb..dedd8c635 100644
--- a/RepoDb.Core/RepoDb/RepoDb.csproj
+++ b/RepoDb.Core/RepoDb/RepoDb.csproj
@@ -3,7 +3,7 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <Authors>Michael Camara Pendon</Authors>
-    <Version>1.12.1</Version>
+    <Version>1.12.3</Version>
     <Company>RepoDb</Company>
     <Product>RepoDb</Product>
     <Description>A hybrid ORM library for .NET.</Description>
@@ -17,8 +17,8 @@
     <NeutralLanguage></NeutralLanguage>
     <PostBuildEvent></PostBuildEvent>
     <PreBuildEvent></PreBuildEvent>
-    <AssemblyVersion>1.12.1.0</AssemblyVersion>
-    <FileVersion>1.12.1.0</FileVersion>
+    <AssemblyVersion>1.12.3.0</AssemblyVersion>
+    <FileVersion>1.12.3.0</FileVersion>
     <GeneratePackageOnBuild>True</GeneratePackageOnBuild>
     <PackageRequireLicenseAcceptance>False</PackageRequireLicenseAcceptance>
     <PackageIconUrl></PackageIconUrl>