コード例 #1
0
        /// <summary>
        ///   Gets the trace session async.
        /// </summary>
        /// <returns> TracingSession if any, null otherwise </returns>
        public async Task<TracingSession> GetTraceSessionAsync()
        {
            TracingSession session = null;
            var sessionCmd = new CqlCommand(_connection,
                                            "select * from system_traces.sessions where session_id=" +
                                            _tracingId.ToString() + ";", CqlConsistency.One);
            using (CqlDataReader<TracingSession> reader = await sessionCmd.ExecuteReaderAsync<TracingSession>().ConfigureAwait(false))
            {
                if (await reader.ReadAsync().ConfigureAwait(false))
                {
                    session = reader.Current;
                }
                else
                    return null;
            }

            var eventsCmd = new CqlCommand(_connection,
                                           "select * from system_traces.events where session_id=" +
                                           _tracingId.ToString() + ";", CqlConsistency.One);
            using (CqlDataReader<TracingEvent> reader = await eventsCmd.ExecuteReaderAsync<TracingEvent>().ConfigureAwait(false))
            {
                var events = new List<TracingEvent>(reader.Count);
                while (await reader.ReadAsync().ConfigureAwait(false))
                {
                    events.Add(reader.Current);
                }

                session.Events = events;
            }

            return session;
        }
コード例 #2
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ファイル: QueryTraceCommand.cs プロジェクト: reuzel/CqlSharp
        /// <summary>
        /// Gets the trace session async.
        /// </summary>
        /// <returns> TracingSession if any, null otherwise </returns>
        public async Task<TracingSession> GetTraceSessionAsync(CancellationToken token)
        {
            TracingSession session;
            var sessionCmd = new CqlCommand(_connection,
                                            "select * from system_traces.sessions where session_id=" +
                                            _tracingId + ";", CqlConsistency.One);
            using(
                CqlDataReader<TracingSession> reader =
                    await sessionCmd.ExecuteReaderAsync<TracingSession>(token).AutoConfigureAwait())
            {
                if(await reader.ReadAsync(token).AutoConfigureAwait())
                    session = reader.Current;
                else
                    return null;
            }

            var eventsCmd = new CqlCommand(_connection,
                                           "select * from system_traces.events where session_id=" +
                                           _tracingId + ";", CqlConsistency.One);
            using(
                CqlDataReader<TracingEvent> reader =
                    await eventsCmd.ExecuteReaderAsync<TracingEvent>(token).AutoConfigureAwait())
            {
                var events = new List<TracingEvent>(reader.Count);
                while(await reader.ReadAsync().AutoConfigureAwait())
                    events.Add(reader.Current);

                session.Events = events;
            }

            return session;
        }
コード例 #3
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        public async Task BasicFlow()
        {
            //Assume
            const string insertCql   = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            const int insertCount = 1000;

            //Act
            using (var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                var executions = new Task <ICqlQueryResult> [insertCount];

                var options = new ParallelOptions()
                {
                    MaxDegreeOfParallelism = 1
                };
                Parallel.For(0, insertCount, options, (i) =>
                {
                    var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                    cmd.Prepare();

                    var b = new BasicFlowData {
                        Id = i, Data = "Hallo " + i
                    };
                    cmd.PartitionKey.Set(b);
                    cmd.Parameters.Set(b);

                    executions[i] = cmd.ExecuteNonQueryAsync();
                });

                await Task.WhenAll(executions);

                var presence = new bool[insertCount];

                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One)
                {
                    EnableTracing = true
                };

                CqlDataReader <BasicFlowData> reader = await selectCmd.ExecuteReaderAsync <BasicFlowData>();

                while (await reader.ReadAsync())
                {
                    BasicFlowData row = reader.Current;
                    Assert.AreEqual(row.Data, "Hallo " + row.Id);
                    presence[row.Id] = true;
                }

                Assert.IsTrue(presence.All(p => p));

                var            tracer  = new QueryTraceCommand(connection, reader.TracingId.Value);
                TracingSession session = await tracer.GetTraceSessionAsync();

                Assert.IsNotNull(session);
            }
        }
コード例 #4
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        /// <summary>
        ///   Queries the cart async.
        /// </summary>
        /// <param name="guid"> The GUID. </param>
        /// <returns> </returns>
        public async Task <Dictionary <string, int> > GetItemsAsync(Guid guid)
        {
            using (var connection = new CqlConnection("cartDB"))
            {
                await connection.OpenAsync();

                var command = new CqlCommand(connection, "select Items from Shop.Carts where id=?;");
                await command.PrepareAsync();

                command.UseBuffering     = true;
                command.Parameters["id"] = guid;
                using (var reader = await command.ExecuteReaderAsync())
                {
                    return(await reader.ReadAsync() ? (Dictionary <string, int>)reader["items"] : null);
                }
            }
        }
コード例 #5
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        /// <summary>
        ///   Finds the carts by group id async.
        /// </summary>
        /// <param name="groupId"> The group id. </param>
        /// <returns> </returns>
        public async Task <List <Cart> > FindCartsByGroupIdAsync(string groupId)
        {
            using (var connection = new CqlConnection("cartDB"))
            {
                await connection.OpenAsync();

                var command = new CqlCommand(connection, "select * from Shop.Carts where GroupId=?;");
                await command.PrepareAsync();

                command.UseBuffering          = true;
                command.Parameters["groupid"] = groupId;
                using (var reader = await command.ExecuteReaderAsync <Cart>())
                {
                    var carts = new List <Cart>();
                    while (await reader.ReadAsync())
                    {
                        carts.Add(reader.Current);
                    }
                    return(carts);
                }
            }
        }
コード例 #6
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        /// <summary>
        ///   Gets the trace session async.
        /// </summary>
        /// <returns> TracingSession if any, null otherwise </returns>
        public async Task <TracingSession> GetTraceSessionAsync()
        {
            TracingSession session    = null;
            var            sessionCmd = new CqlCommand(_connection,
                                                       "select * from system_traces.sessions where session_id=" +
                                                       _tracingId.ToString() + ";", CqlConsistency.One);

            using (CqlDataReader <TracingSession> reader = await sessionCmd.ExecuteReaderAsync <TracingSession>().ConfigureAwait(false))
            {
                if (await reader.ReadAsync().ConfigureAwait(false))
                {
                    session = reader.Current;
                }
                else
                {
                    return(null);
                }
            }

            var eventsCmd = new CqlCommand(_connection,
                                           "select * from system_traces.events where session_id=" +
                                           _tracingId.ToString() + ";", CqlConsistency.One);

            using (CqlDataReader <TracingEvent> reader = await eventsCmd.ExecuteReaderAsync <TracingEvent>().ConfigureAwait(false))
            {
                var events = new List <TracingEvent>(reader.Count);
                while (await reader.ReadAsync().ConfigureAwait(false))
                {
                    events.Add(reader.Current);
                }

                session.Events = events;
            }

            return(session);
        }
コード例 #7
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task BasicPrepareInsertSelect()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                await cmd.PrepareAsync();

                var b = new BasicFlowData {Id = 123, Data = "Hallo", Ignored = "none"};
                cmd.PartitionKey.Set(b);
                cmd.Parameters.Set(b);

                await cmd.ExecuteNonQueryAsync();

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One) {EnableTracing = true};
                await selectCmd.PrepareAsync();

                CqlDataReader<BasicFlowData> reader = await selectCmd.ExecuteReaderAsync<BasicFlowData>();
                Assert.AreEqual(1, reader.Count);
                if(await reader.ReadAsync())
                {
                    BasicFlowData row = reader.Current;
                    Assert.AreEqual(123, row.Id);
                    Assert.AreEqual("Hallo", row.Data);
                    Assert.IsNull(row.Ignored);
                }
                else
                    Assert.Fail("Read should have succeeded");
                }
            }
コード例 #8
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task QueryWithBoundParameters()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //define command
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);

                //add parameters, infer Cql types
                cmd.Parameters.Add("id", 123);
                cmd.Parameters.Add("value", "Hallo");

                try
                {
                    //execute
                    await cmd.ExecuteNonQueryAsync();
                }
                catch(InvalidException)
                {
                    Assert.IsNotNull(connection.ServerVersion);
                    if(String.Compare(connection.ServerVersion, "2.0.0", StringComparison.Ordinal) < 0)
                        return;

                    throw;
                }

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);

                CqlDataReader<BasicFlowData> reader = await selectCmd.ExecuteReaderAsync<BasicFlowData>();
                Assert.AreEqual(1, reader.Count);
                if(await reader.ReadAsync())
                {
                    BasicFlowData row = reader.Current;
                    Assert.AreEqual(123, row.Id);
                    Assert.AreEqual("Hallo", row.Data);
                    Assert.IsNull(row.Ignored);
                }
                else
                    Assert.Fail("Read should have succeeded");
                }
            }
コード例 #9
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task InsertSelectCustomParameters()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                cmd.Parameters.Add("myKey", CqlType.Int);
                cmd.Parameters.Add("myValue", CqlType.Text);
                await cmd.PrepareAsync();

                cmd.Parameters["myKey"].Value = 1234;
                cmd.Parameters["myValue"].Value = "Hallo 1234";
                await cmd.ExecuteNonQueryAsync();

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);

                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();
                Assert.AreEqual(1, reader.Count);
                if(await reader.ReadAsync())
                {
                    Assert.AreEqual(1234, reader["id"]);
                    Assert.AreEqual("Hallo 1234", reader["value"]);
                    Assert.AreEqual(DBNull.Value, reader["ignored"]);
                }
                else
                    Assert.Fail("Read should have succeeded");
                }
            }
コード例 #10
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task TransactionRolledBackDoesNotInsertData()
        {
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (9876, 'Transaction 9876');";
            const string retrieveCql = @"select id from Test.BasicFlow where id=9876;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //create transaction
                using(var transaction = connection.BeginTransaction())
                {
                    //insert data
                    var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                    cmd.Transaction = transaction;
                    await cmd.ExecuteNonQueryAsync();

                    transaction.Rollback();
                }

                //check if data exists
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);
                using(CqlDataReader reader = await selectCmd.ExecuteReaderAsync())
                {
                    //check if any rows are returned
                    Assert.IsFalse(reader.HasRows);
                }
            }
        }
コード例 #11
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ファイル: QueryTests.cs プロジェクト: priyaparul/CqlSharp
        public async Task BasicFlow()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            const int insertCount = 1000;

            //Act
            using (var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                var executions = new Task<ICqlQueryResult>[insertCount];

                var options = new ParallelOptions() { MaxDegreeOfParallelism = 1 };
                Parallel.For(0, insertCount, options, (i) =>
                {
                    var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                    cmd.Prepare();

                    var b = new BasicFlowData { Id = i, Data = "Hallo " + i };
                    cmd.PartitionKey.Set(b);
                    cmd.Parameters.Set(b);

                    executions[i] = cmd.ExecuteNonQueryAsync();
                });

                await Task.WhenAll(executions);

                var presence = new bool[insertCount];

                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One) { EnableTracing = true };

                CqlDataReader<BasicFlowData> reader = await selectCmd.ExecuteReaderAsync<BasicFlowData>();
                while (await reader.ReadAsync())
                {
                    BasicFlowData row = reader.Current;
                    Assert.AreEqual(row.Data, "Hallo " + row.Id);
                    presence[row.Id] = true;
                }

                Assert.IsTrue(presence.All(p => p));

                var tracer = new QueryTraceCommand(connection, reader.TracingId.Value);
                TracingSession session = await tracer.GetTraceSessionAsync();

                Assert.IsNotNull(session);
            }
        }
コード例 #12
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task BatchPreparedWithNamedParameters()
        {
            //Assume
            const string insertCql =
                @"begin batch insert into Test.BasicFlow (id,value) values (:id1,:value1); insert into Test.BasicFlow (id,value) values (:id2,:value2); apply batch;";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //skip if cqlversion too low
                if(string.CompareOrdinal(connection.CqlVersion, "3.1.1") < 0)
                    return;

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                await cmd.PrepareAsync();

                cmd.Parameters["id1"].Value = 0;
                cmd.Parameters["value1"].Value = "Hello 0";
                cmd.Parameters["id2"].Value = 1;
                cmd.Parameters["value2"].Value = "Hello 1";
                await cmd.ExecuteNonQueryAsync();

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);

                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();
                Assert.AreEqual(2, reader.Count);

                var results = new bool[2];
                for(int i = 0; i < 2; i++)
                {
                    if(await reader.ReadAsync())
                    {
                        results[(int)reader["id"]] = true;
                        Assert.AreEqual("Hello " + reader["id"], reader["value"]);
                    }
                    else
                        Assert.Fail("Read should have succeeded");
                    }

                Assert.IsTrue(results.All(p => p));
            }
        }
コード例 #13
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ファイル: CartManager.cs プロジェクト: priyaparul/CqlSharp
        /// <summary>
        ///   Queries the cart async.
        /// </summary>
        /// <param name="guid"> The GUID. </param>
        /// <returns> </returns>
        public async Task<Dictionary<string, int>> GetItemsAsync(Guid guid)
        {
            using (var connection = new CqlConnection("cartDB"))
            {
                await connection.OpenAsync();

                var command = new CqlCommand(connection, "select Items from Shop.Carts where id=?;");
                await command.PrepareAsync();
                command.UseBuffering = true;
                command.Parameters["id"] = guid;
                using (var reader = await command.ExecuteReaderAsync())
                {
                    return await reader.ReadAsync() ? (Dictionary<string, int>) reader["items"] : null;
                }
            }
        }
コード例 #14
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ファイル: CartManager.cs プロジェクト: priyaparul/CqlSharp
        /// <summary>
        ///   Finds the carts by group id async.
        /// </summary>
        /// <param name="groupId"> The group id. </param>
        /// <returns> </returns>
        public async Task<List<Cart>> FindCartsByGroupIdAsync(string groupId)
        {
            using (var connection = new CqlConnection("cartDB"))
            {
                await connection.OpenAsync();

                var command = new CqlCommand(connection, "select * from Shop.Carts where GroupId=?;");
                await command.PrepareAsync();
                command.UseBuffering = true;
                command.Parameters["groupid"] = groupId;
                using (var reader = await command.ExecuteReaderAsync<Cart>())
                {
                    var carts = new List<Cart>();
                    while (await reader.ReadAsync())
                    {
                        carts.Add(reader.Current);
                    }
                    return carts;
                }
            }
        }
コード例 #15
0
ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        private async Task BatchInsertInternal(CqlBatchType batchType)
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select id,value,ignored from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();
                var transaction = connection.BeginTransaction();
                transaction.BatchType = batchType;

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                cmd.Transaction = transaction;

                await cmd.PrepareAsync();

                for(int i = 0; i < 10; i++)
                {
                    cmd.Parameters[0].Value = i;
                    cmd.Parameters[1].Value = "Hello " + i;
                    await cmd.ExecuteNonQueryAsync();
                }

                var cmd2 = new CqlCommand(connection, insertCql, CqlConsistency.One);
                cmd2.Transaction = transaction;
                cmd2.Parameters.Add("id", CqlType.Int);
                cmd2.Parameters.Add("value", CqlType.Text);

                for(int i = 10; i < 20; i++)
                {
                    cmd2.Parameters[0].Value = i;
                    cmd2.Parameters[1].Value = "Hello " + i;
                    await cmd2.ExecuteNonQueryAsync();
                }

                try
                {
                    await transaction.CommitAsync();
                }
                catch(ProtocolException pex)
                {
                    //skip when server version is below 2.0.0
                    if(pex.Code == ErrorCode.Protocol &&
                       String.Compare(connection.ServerVersion, "2.0.0", StringComparison.Ordinal) < 0)
                        return;

                    throw;
                }

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);
                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();
                Assert.AreEqual(20, reader.Count);

                var results = new bool[20];
                for(int i = 0; i < 20; i++)
                {
                    if(await reader.ReadAsync())
                    {
                        results[(int)reader["id"]] = true;
                        Assert.AreEqual("Hello " + reader["id"], reader["value"]);
                    }
                    else
                        Assert.Fail("Read should have succeeded");
                    }

                Assert.IsTrue(results.All(p => p));

                Assert.IsNotNull(transaction.LastBatchResult);
            }
        }
コード例 #16
0
ファイル: MeasurementManager.cs プロジェクト: reuzel/CqlSharp
        /// <summary>
        /// Gets the measurement asynchronous.
        /// </summary>
        /// <param name="id">The identifier.</param>
        /// <returns></returns>
        public static async Task<Measurement> GetMeasurementAsync(int id)
        {
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                var selectCommand = new CqlCommand(connection, "select * from cqlsharptest.measurements where id=?");
                await selectCommand.PrepareAsync();

                selectCommand.Parameters[0].Value = id;

                using(var reader = await selectCommand.ExecuteReaderAsync<Measurement>())
                {
                    return (await reader.ReadAsync()) ? reader.Current : null;
                }
            }
        }
コード例 #17
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ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task SelectWithPagingAsync()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (?,?);";
            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                await cmd.PrepareAsync();

                for(int i = 0; i < 100; i++)
                {
                    cmd.Parameters[0].Value = i;
                    cmd.Parameters[1].Value = "Hello " + i;
                    await cmd.ExecuteNonQueryAsync();
                }

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);
                selectCmd.PageSize = 10;

                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();

                //no paging when version < 2.0.0 is used...
                var expectedCount = String.Compare(connection.ServerVersion, "2.0.0", StringComparison.Ordinal) < 0
                                        ? 100
                                        : 10;
                Assert.AreEqual(expectedCount, reader.Count);

                var results = new bool[100];
                for(int i = 0; i < 100; i++)
                {
                    if(await reader.ReadAsync())
                    {
                        results[(int)reader["id"]] = true;
                        Assert.AreEqual("Hello " + reader["id"], reader["value"]);
                    }
                    else
                        Assert.Fail("Read should have succeeded");
                    }
                Assert.IsFalse(reader.Read());
                Assert.IsTrue(results.All(p => p));
            }
        }
コード例 #18
0
ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task CASInsertSelect()
        {
            //Assume
            const string insertCql = @"insert into Test.BasicFlow (id,value) values (901,'Hallo 901') if not exists;";
            const string insertCql2 = @"insert into Test.BasicFlow (id,value) values (901,'Hallo 901.2') if not exists;";

            const string retrieveCql = @"select * from Test.BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                await connection.OpenAsync();

                //skip when server version is below 2.0.0
                if(String.Compare(connection.ServerVersion, "2.0.0", StringComparison.Ordinal) < 0)
                    return;

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.Any);
                cmd.UseCASLocalSerial = true;
                await cmd.ExecuteNonQueryAsync();
                var result = cmd.LastQueryResult as CqlDataReader;
                Assert.IsNotNull(result);
                Assert.IsTrue(await result.ReadAsync());
                Assert.IsTrue((bool)result["[applied]"]);

                var cmd2 = new CqlCommand(connection, insertCql2, CqlConsistency.Any);
                await cmd2.ExecuteNonQueryAsync();
                var result2 = cmd2.LastQueryResult as CqlDataReader;
                Assert.IsNotNull(result2);
                Assert.IsTrue(await result2.ReadAsync());
                Assert.IsFalse((bool)result2["[applied]"]);
                Assert.AreEqual("Hallo 901", result2["value"]);

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);
                await selectCmd.PrepareAsync();

                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();
                Assert.AreEqual(1, reader.Count);
                if(await reader.ReadAsync())
                {
                    Assert.AreEqual(901, reader["id"]);
                    Assert.AreEqual("Hallo 901", reader["value"]);
                    Assert.AreEqual(DBNull.Value, reader["ignored"]);
                }
                else
                    Assert.Fail("Read should have succeeded");
                }
            }
コード例 #19
0
ファイル: QueryTests.cs プロジェクト: reuzel/CqlSharp
        public async Task ChangeDatabaseThenInsertSelect()
        {
            //Assume
            const string insertCql = @"insert into BasicFlow (id,value) values (901,'Hallo 901');";
            const string retrieveCql = @"select * from BasicFlow;";

            //Act
            using(var connection = new CqlConnection(ConnectionString))
            {
                Assert.AreEqual("", connection.Database);

                await connection.OpenAsync();

                //change database
                connection.ChangeDatabase("test");

                Assert.AreEqual("test", connection.Database);

                //insert data
                var cmd = new CqlCommand(connection, insertCql, CqlConsistency.One);
                await cmd.ExecuteNonQueryAsync();

                //select data
                var selectCmd = new CqlCommand(connection, retrieveCql, CqlConsistency.One);
                CqlDataReader reader = await selectCmd.ExecuteReaderAsync();

                Assert.AreEqual(1, reader.Count);
                if(await reader.ReadAsync())
                {
                    Assert.AreEqual(901, reader["id"]);
                    Assert.AreEqual("Hallo 901", reader["value"]);
                    Assert.AreEqual(DBNull.Value, reader["ignored"]);
                }
                else
                    Assert.Fail("Read should have succeeded");
                }
            }