public static int DeleteFromQuery <T>(this IQueryable <T> querable, BulkDeleteOptions <T> options)
        {
            int rowAffected  = 0;
            var dbQuery      = querable as DbQuery <T>;
            var dbConnection = GetSqlConnectionFromIQuerable(querable);

            //Open datbase connection
            if (dbConnection.State == ConnectionState.Closed)
            {
                dbConnection.Open();
            }

            using (var dbTransaction = dbConnection.BeginTransaction())
            {
                try
                {
                    var sqlQuery = SqlQuery.Parse(dbQuery.Sql);
                    sqlQuery.ChangeToDelete("[Extent1]");
                    rowAffected = SqlUtil.ExecuteSql(sqlQuery.Sql, dbConnection, dbTransaction, options);
                    dbTransaction.Commit();
                }
                catch (Exception ex)
                {
                    dbTransaction.Rollback();
                    throw ex;
                }
                finally
                {
                    dbConnection.Close();
                }
            }
            return(rowAffected);
        }
        public static int BulkDelete <T>(this DbContext context, IEnumerable <T> entities, BulkDeleteOptions <T> options)
        {
            int rowsAffected = 0;
            var tableMapping = context.GetTableMapping(typeof(T));

            Validate(tableMapping);
            var dbConnection = context.GetSqlConnection();

            if (dbConnection.State == ConnectionState.Closed)
            {
                dbConnection.Open();
            }

            using (var transaction = dbConnection.BeginTransaction())
            {
                try
                {
                    string   stagingTableName          = GetStagingTableName(tableMapping, options.UsePermanentTable, dbConnection);
                    string   destinationTableName      = string.Format("[{0}].[{1}]", tableMapping.Schema, tableMapping.TableName);
                    string[] storeGeneratedColumnNames = tableMapping.Columns.Where(o => o.Column.IsStoreGeneratedIdentity).Select(o => o.Column.Name).ToArray();
                    string   deleteCondition           = string.Join(" AND ", storeGeneratedColumnNames.Select(o => string.Format("s.{0}=t.{0}", o)));

                    SqlUtil.CloneTable(destinationTableName, stagingTableName, storeGeneratedColumnNames, dbConnection, transaction);
                    BulkInsert(entities, options, tableMapping, dbConnection, transaction, stagingTableName, storeGeneratedColumnNames, SqlBulkCopyOptions.KeepIdentity);
                    string deleteSql = string.Format("DELETE t FROM {0} s JOIN {1} t ON {2}", stagingTableName, destinationTableName, deleteCondition);
                    rowsAffected = SqlUtil.ExecuteSql(deleteSql, dbConnection, transaction);
                    SqlUtil.DeleteTable(stagingTableName, dbConnection, transaction);
                    transaction.Commit();
                }
                catch (Exception ex)
                {
                    transaction.Rollback();
                    throw ex;
                }
                finally
                {
                    dbConnection.Close();
                }
                return(rowsAffected);
            }
        }