コード例 #1
0
ファイル: DocSamples.cs プロジェクト: kawansoft/AceQL.Client
        /// <summary>
        /// Example of 2 INSERT in the same transaction.
        /// </summary>
        /// <param name="customerId">The customer ID.</param>
        /// <param name="itemId">the item ID.</param>
        /// <exception cref="AceQLException">If any Exception occurs.</exception>
        public async Task InsertCustomerAndOrderLogAsync(int customerId, int itemId)
        {
            // Create a transaction
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            string sql = "insert into customer values " +
                         "(@customer_id, @customer_title, @fname, " +
                         "@lname, @addressline, @town, @zipcode, @phone)";

            try
            {
                AceQLCommand command = new AceQLCommand(sql, connection)
                {
                    Transaction = transaction // Not required, will do nothing.
                };

                command.Parameters.AddWithValue("@customer_id", customerId);
                command.Parameters.AddWithValue("@customer_title", "Sir");
                command.Parameters.AddWithValue("@fname", "John");
                command.Parameters.AddWithValue("@lname", "Doe");
                command.Parameters.AddWithValue("@addressline", "1 Madison Ave");
                command.Parameters.AddWithValue("@town", "New York");
                command.Parameters.AddWithValue("@zipcode", "NY 10010");
                command.Parameters.Add(new AceQLParameter("@phone", new AceQLNullValue(AceQLNullType.VARCHAR)));

                await command.ExecuteNonQueryAsync();

                sql = "insert into orderlog values " +
                      "(@customer_id, @item_id, @description, " +
                      "@item_cost, @date_placed, @date_shipped, " +
                      "@jpeg_image, @is_delivered, @quantity)";

                command = new AceQLCommand(sql, connection);

                AceQLConsole.WriteLine("insert into orderlog...");

                command.Parameters.AddWithValue("@customer_id", customerId);
                command.Parameters.AddWithValue("@item_id", itemId);
                command.Parameters.AddWithValue("@description", "Item Description");
                command.Parameters.AddWithValue("@item_cost", 99D);
                command.Parameters.AddWithValue("@date_placed", DateTime.Now);
                command.Parameters.AddWithValue("@date_shipped", DateTime.Now);
                // No blob for now
                command.Parameters.Add(new AceQLParameter("@jpeg_image", new AceQLNullValue(AceQLNullType.BLOB)));
                command.Parameters.AddWithValue("@is_delivered", 1);
                command.Parameters.AddWithValue("@quantity", 1);

                await command.ExecuteNonQueryAsync();

                await transaction.CommitAsync();
            }
            catch (Exception e)
            {
                // Transaction must always be terminated by a CommitAsync() or RollbackAsync()
                await transaction.RollbackAsync();

                throw;
            }
        }
コード例 #2
0
        /// <summary>
        /// Example of 2 INSERT in the same transaction.
        /// </summary>
        /// <param name="customerId">The customer ID.</param>
        /// <param name="itemId">the item ID.</param>
        /// <exception cref="AceQLException">If any Exception occurs.</exception>
        public async Task InsertCustomerAndOrderLogAsync(int customerId, int itemId)
        {
            // Create a transaction
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            string sql = "insert into customer values " + "" +
                         "(@parm1, @parm2, @parm3, @parm4, @parm5, @parm6, @parm7, @parm8)";

            AceQLCommand command = new AceQLCommand(sql, connection);

            try
            {
                command.Parameters.AddWithValue("@parm1", customerId);
                command.Parameters.AddWithValue("@parm2", "Sir");
                command.Parameters.AddWithValue("@parm3", "Doe");
                command.Parameters.AddWithValue("@parm4", "John");
                // Alternate syntax
                command.Parameters.Add(new AceQLParameter("@parm5", "1 Madison Ave"));
                command.Parameters.AddWithValue("@parm6", "New York");
                command.Parameters.AddWithValue("@parm7", "NY 10010");

                command.Parameters.Add(new AceQLParameter("@parm8", new AceQLNullValue(AceQLNullType.VARCHAR)));

                await command.ExecuteNonQueryAsync();

                sql = "insert into orderlog values " +
                      "(@customer_id, @item_id, @description, " +
                      "@item_cost, @date_placed, @date_shipped, " +
                      "@jpeg_image, @is_delivered, @quantity)";

                command = new AceQLCommand(sql, connection);

                command.Parameters.AddWithValue("@customer_id", customerId);
                command.Parameters.AddWithValue("@item_id", itemId);
                command.Parameters.AddWithValue("@description", "Item Description");
                command.Parameters.AddWithValue("@item_cost", 99D);
                command.Parameters.AddWithValue("@date_placed", DateTime.Now);
                command.Parameters.AddWithValue("@date_shipped", DateTime.Now);

                // No BLOB in our Quick start
                command.Parameters.Add(new AceQLParameter("@jpeg_image", new AceQLNullValue(AceQLNullType.BLOB)));
                command.Parameters.AddWithValue("@is_delivered", 1);
                command.Parameters.AddWithValue("@quantity", 1);

                await command.ExecuteNonQueryAsync();

                await transaction.CommitAsync();
            }
            catch (Exception e)
            {
                await transaction.RollbackAsync();

                throw;
            }
        }
コード例 #3
0
        /// <summary>
        /// Example of an SELECT of a BLOB
        /// </summary>
        /// <param name="customerId">The customer ID.</param>
        /// <param name="itemId">the item ID.</param>
        /// <exception cref="AceQLException">If any Exception occurs.</exception>
        public async Task SelectBlob(int customerId, int itemId)
        {
            // Create a transaction because some database engines require autocommit off
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            try
            {
                string sql = "select customer_id, item_id, jpeg_image from orderlog" +
                             " where customer_id =  @customer_id and item_id = @item_id";

                AceQLCommand command = new AceQLCommand(sql, connection);
                command.Parameters.AddWithValue("@customer_id", customerId);
                command.Parameters.AddWithValue("@item_id", itemId);

                using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
                {
                    while (dataReader.Read())
                    {
                        int i = 0;
                        AceQLConsole.WriteLine("customer_id   : " + dataReader.GetValue(i++));
                        AceQLConsole.WriteLine("item_id: " + dataReader.GetValue(i++));

                        string userPath =
                            Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
                        string blobPath = userPath + "\\koala_download.jpg";

                        AceQLConsole.WriteLine("Creating file from server BLOB in: " + blobPath);

                        // Download Blob
                        using (Stream stream = await dataReader.GetStreamAsync(i++))
                        {
                            using (var fileStream = File.Create(blobPath))
                            {
                                stream.CopyTo(fileStream);
                            }
                        }
                    }

                    await transaction.CommitAsync();
                }
            }
            catch (Exception e)
            {
                // Transaction must always be terminated by a CommitAsync() or RollbackAsync()
                await transaction.RollbackAsync();

                throw e;
            }
        }
コード例 #4
0
        /// <summary>
        /// Example of an INSERT of a BLOB
        /// </summary>
        /// <param name="customerId">The customer ID.</param>
        /// <param name="itemId">the item ID.</param>
        /// <exception cref="AceQLException">If any Exception occurs.</exception>
        public async Task InsertBlobProgressIndicator(int customerId, int itemId)
        {
            // Create a transaction because some database engines require autocommit off
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            try
            {
                string sql = "insert into orderlog values " +
                             "(@customer_id, @item_id, @description, " +
                             "@item_cost, @date_placed, @date_shipped, " +
                             "@jpeg_image, @is_delivered, @quantity)";

                AceQLCommand command = new AceQLCommand(sql, connection);

                string userPath =
                    Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
                string blobPath = userPath + "\\koala.jpg";
                Stream stream   = new FileStream(blobPath, FileMode.Open, FileAccess.Read);
                long   length   = new FileInfo(blobPath).Length;

                AceQLConsole.WriteLine("blobPath: " + blobPath);
                AceQLConsole.WriteLine("insert into orderlog...");

                command.Parameters.AddWithValue("@customer_id", customerId);
                command.Parameters.AddWithValue("@item_id", itemId);
                command.Parameters.AddWithValue("@description", "Item Description");
                command.Parameters.AddWithValue("@item_cost", 99D);
                command.Parameters.AddWithValue("@date_placed", DateTime.Now);
                command.Parameters.AddWithValue("@date_shipped", DateTime.Now);
                command.Parameters.AddWithValue("@jpeg_image", stream, length);
                command.Parameters.AddWithValue("@is_delivered", 1);
                command.Parameters.AddWithValue("@quantity", 1);

                AceQLProgressIndicator progressIndicator = new AceQLProgressIndicator();
                connection.SetProgressIndicator(progressIndicator);

                await command.ExecuteNonQueryAsync();

                await transaction.CommitAsync();
            }
            catch (Exception e)
            {
                // Transaction must always be terminated by a CommitAsync() or RollbackAsync()
                await transaction.RollbackAsync();

                throw e;
            }
        }
コード例 #5
0
        /// <summary>
        /// Inserts an image into a product_image using a stream.
        /// </summary>
        /// <param name="productId">The product identifier.</param>
        /// <param name="productName">Name of the product.</param>
        /// <param name="stream">The stream.</param>
        /// <returns>Task.</returns>
        public async Task InsertIntoProductAsync(int productId, string productName, Stream stream)
        {
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            try
            {
                String sql =
                    "insert into product_image values (@product_id,  @name, @image)";

                AceQLCommand command = new AceQLCommand(sql, connection);
                command.Parameters.AddWithValue("@product_id", productId);
                command.Parameters.AddWithValue("@name", productName);
                command.Parameters.AddWithValue("@image", stream);

                await command.ExecuteNonQueryAsync();
            }
            finally
            {
                await transaction.CommitAsync();
            }
        }
コード例 #6
0
        /// <summary>
        /// Returns a Stream on the blob in product_image table
        /// </summary>
        /// <param name="productId"></param>
        /// <returns></returns>
        public async Task <Stream> SelectProductImageAsync(int productId)
        {
            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            Stream stream = null;

            try
            {
                String       sql     = "select image from product_image where product_id = @product_id";
                AceQLCommand command = new AceQLCommand(sql, connection);
                command.Parameters.AddWithValue("@product_id", productId);

                using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
                {
                    while (dataReader.Read())
                    {
                        stream = await dataReader.GetStreamAsync(0);
                    }

                    await transaction.CommitAsync();
                }
            }
            catch (Exception e)
            {
                try
                {
                    await transaction.RollbackAsync();
                }
                catch (Exception)
                {
                    // Don't care
                }

                throw e;
            }

            return(stream);
        }
コード例 #7
0
        /// <summary>
        /// Executes our example using an <see cref="AceQLConnection"/>
        /// </summary>
        /// <param name="connection"></param>
        private static async Task ExecuteExample(AceQLConnection connection)
        {
            await connection.OpenAsync();

            AceQLConsole.WriteLine("host: " + connection.ConnectionInfo.ConnectionString);
            AceQLConsole.WriteLine("aceQLConnection.GetClientVersion(): " + AceQLConnection.GetClientVersion());
            AceQLConsole.WriteLine("aceQLConnection.GetServerVersion(): " + await connection.GetServerVersionAsync());
            AceQLConsole.WriteLine("AceQL local folder: ");
            AceQLConsole.WriteLine(AceQLConnection.GetAceQLLocalFolder());

            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            await transaction.CommitAsync();

            transaction.Dispose();

            string sql = "delete from customer_2";

            AceQLCommand command = new AceQLCommand
            {
                CommandText = sql,
                Connection  = connection
            };

            command.Prepare();

            await command.ExecuteNonQueryAsync();

            for (int i = 0; i < 3; i++)
            {
                sql =
                    "insert into customer_2 values (@parm1, @parm2, @parm3, @parm4, @parm5, @parm6, @parm7, @parm8, @parm9, @parm_10)";

                command = new AceQLCommand(sql, connection);

                int customer_id = i;

                command.Parameters.AddWithValue("@parm1", customer_id);
                command.Parameters.AddWithValue("@parm2", "Sir");
                command.Parameters.AddWithValue("@parm3", "André_" + customer_id);
                command.Parameters.Add(new AceQLParameter("@parm4", "Name_" + customer_id));
                command.Parameters.AddWithValue("@parm5", customer_id + ", road 66");
                command.Parameters.AddWithValue("@parm6", "Town_" + customer_id);
                command.Parameters.AddWithValue("@parm7", customer_id + "1111");
                command.Parameters.Add(new AceQLParameter("@parm8", AceQLNullType.VARCHAR)); //null value for NULL SQL insert.
                command.Parameters.AddWithValue("@parm9", customer_id + "_row_2");
                command.Parameters.AddWithValue("@parm_10", customer_id + "_row_count");

                CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
                await command.ExecuteNonQueryAsync(cancellationTokenSource.Token);
            }

            command.Dispose();

            sql     = "select * from customer_2";
            command = new AceQLCommand(sql, connection);

            // Our dataReader must be disposed to delete underlying downloaded files
            using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
            {
                while (dataReader.Read())
                {
                    AceQLConsole.WriteLine();
                    int i = 0;
                    AceQLConsole.WriteLine("GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i));
                }
            }

            AceQLConsole.WriteLine("Done.");
        }
コード例 #8
0
        /// <summary>
        /// Executes our example using an <see cref="AceQLConnection"/>
        /// </summary>
        /// <param name="connection"></param>
        private static async Task ExecuteExample(AceQLConnection connection)
        {
            //Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
            string IN_DIRECTORY  = "c:\\test\\";
            string OUT_DIRECTORY = "c:\\test\\out\\";

            await connection.OpenAsync();

            AceQLConsole.WriteLine("AceQLConnection.GetClientVersion(): " + AceQLConnection.GetClientVersion());
            AceQLConsole.WriteLine("AceQLConnection.GetServerVersion(): " + await connection.GetServerVersionAsync());
            AceQLConsole.WriteLine("AceQL local folder: ");
            AceQLConsole.WriteLine(await AceQLConnection.GetAceQLLocalFolderAsync());

            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            await transaction.CommitAsync();

            transaction.Dispose();

            AceQLConsole.WriteLine("Before delete from orderlog");

            // Do next delete in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            string       sql     = "delete from orderlog";
            AceQLCommand command = new AceQLCommand(sql, connection);
            await command.ExecuteNonQueryAsync();

            command.Dispose();

            await transaction.CommitAsync();

            // Do next inserts in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            AceQLConsole.WriteLine("Before insert into orderlog");
            try
            {
                sql =
                    "insert into orderlog values (@parm1, @parm2, @parm3, @parm4, @parm5, @parm6, @parm7, @parm8, @parm9)";

                command = new AceQLCommand(sql, connection);

                int customer_id = 1;

                string blobPath = IN_DIRECTORY + "username_koala.jpg";
                Stream stream   = new FileStream(blobPath, FileMode.Open, System.IO.FileAccess.Read);

                //customer_id integer NOT NULL,
                //item_id integer NOT NULL,
                //description character varying(64) NOT NULL,
                //cost_price numeric,
                //date_placed date NOT NULL,
                //date_shipped timestamp without time zone,
                //jpeg_image oid,
                //is_delivered numeric,
                //quantity integer NOT NULL,

                command.Parameters.AddWithValue("@parm1", customer_id);
                command.Parameters.AddWithValue("@parm2", customer_id);
                command.Parameters.AddWithValue("@parm3", "Description_" + customer_id);

                command.Parameters.Add(new AceQLParameter("@parm4", new AceQLNullValue(AceQLNullType.DECIMAL))); //null value for NULL SQL insert.

                command.Parameters.AddWithValue("@parm5", DateTime.Now);
                command.Parameters.AddWithValue("@parm6", DateTime.Now);
                // Adds the Blob. (Stream will be closed by AceQLCommand)
                command.Parameters.AddWithValue("@parm7", stream);
                command.Parameters.AddWithValue("@parm8", 1);
                command.Parameters.AddWithValue("@parm9", 1 * 2000);

                await command.ExecuteNonQueryAsync();

                await transaction.CommitAsync();
            }
            catch (Exception exception)
            {
                await transaction.RollbackAsync();

                throw exception;
            }

            AceQLConsole.WriteLine("Before select *  from orderlog");

            // Do next selects in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            sql     = "select * from orderlog where cutomer_id = 1 and order_id = 1";
            command = new AceQLCommand(sql, connection);

            using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
            {
                int k = 0;
                while (dataReader.Read())
                {
                    AceQLConsole.WriteLine();
                    int i = 0;
                    AceQLConsole.WriteLine("GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++));

                    // Download Blobs
                    string blobPath = OUT_DIRECTORY + "username_koala_" + k + ".jpg";
                    k++;

                    using (Stream stream = await dataReader.GetStreamAsync(6))
                    {
                        using (var fileStream = File.Create(blobPath))
                        {
                            //stream.CopyTo(fileStream);
                            CopyStream(stream, fileStream);
                        }
                    }
                }
            }

            await transaction.CommitAsync();
        }
コード例 #9
0
        /// <summary>
        /// Executes our example using an <see cref="AceQLConnection"/>
        /// </summary>
        /// <param name="connection"></param>
        private static async Task ExecuteExample(AceQLConnection connection)
        {
            string IN_DIRECTORY  = AceQLConnection.GetAceQLLocalFolder() + "\\";
            string OUT_DIRECTORY = IN_DIRECTORY + "out\\";

            _ = Directory.CreateDirectory(OUT_DIRECTORY);

            await connection.OpenAsync();

            AceQLConsole.WriteLine("ConnectionString: " + connection.ConnectionInfo.ConnectionString);
            AceQLConsole.WriteLine();
            AceQLConsole.WriteLine("AceQLConnection.GetClientVersion(): " + AceQLConnection.GetClientVersion());
            AceQLConsole.WriteLine("AceQLConnection.GetServerVersion(): " + await connection.GetServerVersionAsync());
            AceQLConsole.WriteLine("AceQL local folder: ");
            AceQLConsole.WriteLine(AceQLConnection.GetAceQLLocalFolder());

            if (!CONSOLE_INPUT_DONE)
            {
                AceQLConsole.WriteLine();
                AceQLConsole.WriteLine("Press enter to close....");
                Console.ReadLine();
                CONSOLE_INPUT_DONE = true;
            }

            AceQLTransaction transaction = await connection.BeginTransactionAsync();

            await transaction.CommitAsync();

            transaction.Dispose();

            string sql = "delete from customer";

            AceQLCommand command = null;

            command = new AceQLCommand()
            {
                CommandText = sql,
                Connection  = connection
            };
            command.Prepare();

            await command.ExecuteNonQueryAsync();

            sql = "delete from dustomer";

            command = new AceQLCommand()
            {
                CommandText = sql,
                Connection  = connection
            };
            command.Prepare();

            try
            {
                await command.ExecuteNonQueryAsync();
            }
            catch (Exception exception)
            {
                AceQLConsole.WriteLine(exception.ToString());
            }

            sql     = "delete from dustomer where customer_id = @parm1 or fname = @parm2  ";
            command = new AceQLCommand()
            {
                CommandText = sql,
                Connection  = connection
            };
            command.Parameters.AddWithValue("@parm1", 1);
            command.Parameters.AddWithValue("@parm2", "Doe");

            try
            {
                await command.ExecuteNonQueryAsync();
            }
            catch (Exception exception)
            {
                AceQLConsole.WriteLine(exception.ToString());
            }



            for (int i = 0; i < 3; i++)
            {
                sql =
                    "insert into customer values (@parm1, @parm2, @parm3, @parm4, @parm5, @parm6, @parm7, @parm8)";

                command = new AceQLCommand(sql, connection);

                int customer_id = i;

                command.Parameters.AddWithValue("@parm1", customer_id);
                command.Parameters.AddWithValue("@parm2", "Sir");
                command.Parameters.AddWithValue("@parm3", "André_" + customer_id);
                command.Parameters.Add(new AceQLParameter("@parm4", "Name_" + customer_id));
                command.Parameters.AddWithValue("@parm5", customer_id + ", road 66");
                command.Parameters.AddWithValue("@parm6", "Town_" + customer_id);
                command.Parameters.AddWithValue("@parm7", customer_id + "1111");
                command.Parameters.Add(new AceQLParameter("@parm8", new AceQLNullValue(AceQLNullType.VARCHAR))); //null value for NULL SQL insert.

                CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
                await command.ExecuteNonQueryAsync(cancellationTokenSource.Token);
            }

            command.Dispose();

            sql     = "select * from customer";
            command = new AceQLCommand(sql, connection);

            // Our dataReader must be disposed to delete underlying downloaded files
            using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
            {
                //await dataReader.ReadAsync(new CancellationTokenSource().Token)
                while (dataReader.Read())
                {
                    AceQLConsole.WriteLine();
                    int i = 0;
                    AceQLConsole.WriteLine("GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++));
                }
            }

            AceQLConsole.WriteLine("Before delete from orderlog 2");

            // Do next delete in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            sql     = "delete from orderlog";
            command = new AceQLCommand(sql, connection);
            await command.ExecuteNonQueryAsync();

            command.Dispose();

            AceQLConsole.WriteLine("After delete from orderlog 2");

            await transaction.CommitAsync();

            Boolean doBlob = true;

            if (!doBlob)
            {
                return;
            }

            // Do next inserts in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            try
            {
                for (int j = 1; j < 4; j++)
                {
                    sql =
                        "insert into orderlog values (@parm1, @parm2, @parm3, @parm4, @parm5, @parm6, @parm7, @parm8, @parm9)";

                    command = new AceQLCommand(sql, connection);

                    int customer_id = j;

                    string blobPath = null;

                    int index = getIndexFromDatabase();
                    blobPath = IN_DIRECTORY + "username_koala_" + index + ".jpg";

                    Stream stream = new FileStream(blobPath, FileMode.Open, System.IO.FileAccess.Read);

                    //customer_id integer NOT NULL,
                    //item_id integer NOT NULL,
                    //description character varying(64) NOT NULL,
                    //cost_price numeric,
                    //date_placed date NOT NULL,
                    //date_shipped timestamp without time zone,
                    //jpeg_image oid,
                    //is_delivered numeric,
                    //quantity integer NOT NULL,

                    command.Parameters.AddWithValue("@parm1", customer_id);
                    command.Parameters.AddWithValue("@parm2", customer_id);
                    command.Parameters.AddWithValue("@parm3", "Description_" + customer_id);
                    command.Parameters.Add(new AceQLParameter("@parm4", new AceQLNullValue(AceQLNullType.DECIMAL))); //null value for NULL SQL insert.
                    command.Parameters.AddWithValue("@parm5", DateTime.Now);
                    command.Parameters.AddWithValue("@parm6", DateTime.Now);
                    // Adds the Blob. (Stream will be closed by AceQLCommand)

                    command.Parameters.AddWithValue("@parm7", stream);

                    command.Parameters.AddWithValue("@parm8", 1);
                    command.Parameters.AddWithValue("@parm9", j * 2000);

                    AceQLConsole.WriteLine("Before await command.ExecuteNonQueryAsync()");
                    await command.ExecuteNonQueryAsync();

                    AceQLConsole.WriteLine("After await command.ExecuteNonQueryAsync()");
                }

                AceQLConsole.WriteLine("transaction.CommitAsync()");
                await transaction.CommitAsync();
            }
            catch (Exception)
            {
                await transaction.RollbackAsync();

                throw;
            }

            AceQLConsole.WriteLine("Before select *  from orderlog");

            // Do next selects in a transaction because of BLOB
            transaction = await connection.BeginTransactionAsync();

            sql     = "select * from orderlog";
            command = new AceQLCommand(sql, connection);

            using (AceQLDataReader dataReader = await command.ExecuteReaderAsync())
            {
                int k = 0;
                while (dataReader.Read())
                {
                    AceQLConsole.WriteLine();
                    int i = 0;
                    AceQLConsole.WriteLine("Get values using ordinal values:");
                    AceQLConsole.WriteLine("GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++) + "\n"
                                           + "GetValue: " + dataReader.GetValue(i++));

                    //customer_id
                    //item_id
                    //description
                    //item_cost
                    //date_placed
                    //date_shipped
                    //jpeg_image
                    //is_delivered
                    //quantity

                    AceQLConsole.WriteLine();
                    AceQLConsole.WriteLine("Get values using column name values:");
                    AceQLConsole.WriteLine("GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("customer_id"))
                                           + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("item_id")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("description")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("item_cost")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("date_placed")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("date_shipped")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("jpeg_image")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("is_delivered")) + "\n"
                                           + "GetValue: " + dataReader.GetValue(dataReader.GetOrdinal("quantity")));

                    AceQLConsole.WriteLine("==> dataReader.IsDBNull(3): " + dataReader.IsDBNull(3));
                    AceQLConsole.WriteLine("==> dataReader.IsDBNull(4): " + dataReader.IsDBNull(4));

                    // Download Blobs
                    int    index    = getIndexFromDatabase();
                    string blobPath = OUT_DIRECTORY + "username_koala_" + index + "_" + k + ".jpg";
                    k++;

                    using (Stream stream = await dataReader.GetStreamAsync(6))
                    {
                        using (var fileStream = File.Create(blobPath))
                        {
                            stream.CopyTo(fileStream);
                        }
                    }
                }
            }

            await transaction.CommitAsync();
        }