Exemplo n.º 1
0
    def short_read_delete_test(self):
        """ Test short reads ultimately leaving no columns alive [#4000] """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfere with the test
        cluster.set_configuration_options(values={'hinted_handoff_enabled': False})
        cluster.set_batch_commitlog(enabled=True)

        cluster.populate(2).start(wait_other_notice=True)
        node1, node2 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 3)
        self.create_cf(session, 'cf', read_repair=0.0)
        # insert 2 columns in one row
        insert_columns(self, session, 0, 2)

        # Delete the row while first node is dead
        node1.flush()
        node1.stop(wait_other_notice=True)
        session = self.patient_cql_connection(node2, 'ks')

        query = SimpleStatement('DELETE FROM cf WHERE key=\'k0\'', consistency_level=ConsistencyLevel.ONE)
        session.execute(query)

        node1.start(wait_other_notice=True)

        # Query first column
        session = self.patient_cql_connection(node1, 'ks')

        assert_none(session, "SELECT c, v FROM cf WHERE key=\'k0\' LIMIT 1", cl=ConsistencyLevel.QUORUM)
    def short_read_delete_test(self):
        """ Test short reads ultimately leaving no columns alive [#4000] """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={"hinted_handoff_enabled": False}, batch_commitlog=True)

        cluster.populate(2).start(wait_other_notice=True)
        node1, node2 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, "ks", 3)
        self.create_cf(session, "cf", read_repair=0.0)
        # insert 2 columns in one row
        insert_columns(self, session, 0, 2)

        # Delete the row while first node is dead
        node1.flush()
        node1.stop(wait_other_notice=True)
        session = self.patient_cql_connection(node2, "ks")

        query = SimpleStatement("DELETE FROM cf WHERE key='k0'", consistency_level=ConsistencyLevel.ONE)
        session.execute(query)

        node1.start(wait_other_notice=True)

        # Query first column
        session = self.patient_cql_connection(node1, "ks")

        query = SimpleStatement("SELECT c, v FROM cf WHERE key='k0' LIMIT 1", consistency_level=ConsistencyLevel.QUORUM)
        res = session.execute(query)
        assert len(res) == 0, res
Exemplo n.º 3
0
    def short_read_reversed_test(self):
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={ 'hinted_handoff_enabled' : False}, batch_commitlog=True)

        cluster.populate(3).start(wait_other_notice=True)
        [node1, node2, node3] = cluster.nodelist()

        cursor = self.patient_cql_connection(node1)
        self.create_ks(cursor, 'ks', 3)
        self.create_cf(cursor, 'cf', read_repair=0.0)
        # insert 9 columns in one row
        insert_columns(self, cursor, 0, 9)

        # Deleting 3 last columns with a different node dead each time
        self.stop_delete_and_restart(1, 6)
        self.stop_delete_and_restart(2, 7)
        self.stop_delete_and_restart(3, 8)

        # Query 3 firsts columns
        cursor = self.patient_cql_connection(node1, 'ks')
        query = SimpleStatement('SELECT c, v FROM cf WHERE key=\'k0\' ORDER BY c DESC LIMIT 3', consistency_level=ConsistencyLevel.QUORUM)
        rows = cursor.execute(query)
        res = rows
        assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (len(res), str(res))
        # value 6, 7 and 8 have been deleted
        for i in xrange(0, 3):
            assert res[i][1] == 'value%d' % (5-i), 'Expecting value%d, got %s (%s)' % (5-i, res[i][1], str(res))
    def short_read_reversed_test(self):
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(
            values={'hinted_handoff_enabled': False}, batch_commitlog=True)

        cluster.populate(3).start()
        [node1, node2, node3] = cluster.nodelist()
        time.sleep(.5)

        cursor = self.patient_cql_connection(node1).cursor()
        self.create_ks(cursor, 'ks', 3)
        self.create_cf(cursor, 'cf', read_repair=0.0)
        # insert 9 columns in one row
        insert_columns(self, cursor, 0, 9)
        cursor.close()

        # Deleting 3 last columns with a different node dead each time
        self.stop_delete_and_restart(1, 6)
        self.stop_delete_and_restart(2, 7)
        self.stop_delete_and_restart(3, 8)

        # Query 3 firsts columns
        cursor = self.patient_cql_connection(node1, 'ks').cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute(
                'SELECT c, v FROM cf WHERE key=\'k0\' ORDER BY c DESC LIMIT 3',
                consistency_level="QUORUM")
            res = cursor.fetchall()
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (
                len(res), str(res))
            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                assert res[i][1] == 'value%d' % (
                    5 - i), 'Expecting value%d, got %s (%s)' % (
                        5 - i, res[i][1], str(res))
        else:
            cursor.execute(
                'SELECT FIRST 3 REVERSED * FROM cf USING CONSISTENCY QUORUM WHERE key=k0'
            )
            assert cursor.rowcount == 1
            res = cursor.fetchone()
            # the key is returned
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (
                len(res), str(res))
            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                assert res[i] == 'value%d' % (
                    5 - i), 'Expecting value%d, got %s (%s)' % (5 - i, res[i],
                                                                str(res))
    def short_read_delete_test(self):
        """ Test short reads ultimately leaving no columns alive [#4000] """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(
            values={'hinted_handoff_enabled': False}, batch_commitlog=True)

        cluster.populate(2).start()
        [node1, node2] = cluster.nodelist()
        time.sleep(.5)

        cursor = self.patient_cql_connection(node1).cursor()
        self.create_ks(cursor, 'ks', 3)
        self.create_cf(cursor, 'cf', read_repair=0.0)
        # insert 2 columns in one row
        insert_columns(self, cursor, 0, 2)
        cursor.close()

        # Delete the row while first node is dead
        node1.flush()
        node1.stop(wait_other_notice=True)
        cursor = self.patient_cql_connection(node2, 'ks').cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute('DELETE FROM cf WHERE key=\'k0\'',
                           consistency_level="ONE")
        else:
            cursor.execute('DELETE FROM cf USING CONSISTENCY ONE WHERE key=k0')
        cursor.close()
        node1.start(wait_other_notice=True)
        time.sleep(.5)

        # Query first column
        cursor = self.patient_cql_connection(node1, 'ks').cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute('SELECT c, v FROM cf WHERE key=\'k0\' LIMIT 1',
                           consistency_level="QUORUM")
            res = cursor.fetchone()
            assert cursor.rowcount == 0, res
        else:
            cursor.execute(
                'SELECT FIRST 1 * FROM cf USING CONSISTENCY QUORUM WHERE key=k0'
            )
            assert cursor.rowcount == 1
            res = cursor.fetchone()
            assert len(res) == 0, 'Expecting no value, got %d (%s)' % (
                len(res), str(res))
    def short_read_test(self):
        """
        @jira_ticket CASSANDRA-9460
        """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(
            values={'hinted_handoff_enabled': False}, batch_commitlog=True)

        cluster.populate(3).start(wait_other_notice=True)
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 3)
        self.create_cf(session, 'cf', read_repair=0.0)

        # Repeat this test 10 times to make it more easy to spot a null pointer exception caused by a race, see CASSANDRA-9460
        for k in xrange(10):
            # insert 9 columns in one row
            insert_columns(self, session, 0, 9)

            # Deleting 3 first columns with a different node dead each time
            self.stop_delete_and_restart(1, 0)
            self.stop_delete_and_restart(2, 1)
            self.stop_delete_and_restart(3, 2)

            # Query 3 firsts columns
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement(
                'SELECT c, v FROM cf WHERE key=\'k0\' LIMIT 3',
                consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (
                len(res), str(res))
            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                assert res[i - 1][1] == 'value%d' % (
                    i + 2), 'Expecting value%d, got %s (%s)' % (
                        i + 2, res[i - 1][1], str(res))

            truncate_statement = SimpleStatement(
                'TRUNCATE cf', consistency_level=ConsistencyLevel.QUORUM)
            session.execute(truncate_statement)
    def short_read_test(self):
        """
        @jira_ticket CASSANDRA-9460
        """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={"hinted_handoff_enabled": False}, batch_commitlog=True)

        cluster.populate(3).start(wait_other_notice=True)
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, "ks", 3)
        self.create_cf(session, "cf", read_repair=0.0)

        # Repeat this test 10 times to make it more easy to spot a null pointer exception caused by a race, see CASSANDRA-9460
        for k in xrange(10):
            # insert 9 columns in one row
            insert_columns(self, session, 0, 9)

            # Deleting 3 first columns with a different node dead each time
            self.stop_delete_and_restart(1, 0)
            self.stop_delete_and_restart(2, 1)
            self.stop_delete_and_restart(3, 2)

            # Query 3 firsts columns
            session = self.patient_cql_connection(node1, "ks")
            query = SimpleStatement(
                "SELECT c, v FROM cf WHERE key='k0' LIMIT 3", consistency_level=ConsistencyLevel.QUORUM
            )
            rows = session.execute(query)
            res = rows
            assert len(res) == 3, "Expecting 3 values, got %d (%s)" % (len(res), str(res))
            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                assert res[i - 1][1] == "value%d" % (i + 2), "Expecting value%d, got %s (%s)" % (
                    i + 2,
                    res[i - 1][1],
                    str(res),
                )

            truncate_statement = SimpleStatement("TRUNCATE cf", consistency_level=ConsistencyLevel.QUORUM)
            session.execute(truncate_statement)
Exemplo n.º 8
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    def short_read_test(self):
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={"hinted_handoff_enabled": False}, batch_commitlog=True)

        cluster.populate(3).start()
        [node1, node2, node3] = cluster.nodelist()
        time.sleep(0.5)

        cursor = self.patient_cql_connection(node1).cursor()
        self.create_ks(cursor, "ks", 3)
        self.create_cf(cursor, "cf", read_repair=0.0)
        # insert 9 columns in one row
        insert_columns(self, cursor, 0, 9)
        cursor.close()

        # Deleting 3 first columns with a different node dead each time
        self.stop_delete_and_restart(1, 0)
        self.stop_delete_and_restart(2, 1)
        self.stop_delete_and_restart(3, 2)

        # Query 3 firsts columns
        cursor = self.patient_cql_connection(node1, "ks").cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute("SELECT c, v FROM cf WHERE key='k0' LIMIT 3", consistency_level="QUORUM")
            res = cursor.fetchall()
            assert len(res) == 3, "Expecting 3 values, got %d (%s)" % (len(res), str(res))
            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                assert res[i - 1][1] == "value%d" % (i + 2), "Expecting value%d, got %s (%s)" % (
                    i + 2,
                    res[i - 1][1],
                    str(res),
                )
        else:
            cursor.execute("SELECT FIRST 3 * FROM cf USING CONSISTENCY QUORUM WHERE key=k0")
            assert cursor.rowcount == 1
            res = cursor.fetchone()
            # the key is returned
            assert len(res) == 3, "Expecting 3 values, got %d (%s)" % (len(res), str(res))
            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                assert res[i] == "value%d" % (i + 2), "Expecting value%d, got %s (%s)" % (i + 2, res[i], str(res))
Exemplo n.º 9
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    def wide_row_test(self):
        """ Test wide row slices """
        cluster = self.cluster

        cluster.populate(3).start()
        node1, node2, node3 = cluster.nodelist()

        cursor = self.patient_cql_connection(node1)
        self.create_ks(cursor, 'ks', 1)
        self.create_cf(cursor, 'cf')

        key = 'wide'

        for x in xrange(1, 5001):
            tools.insert_columns(self, cursor, key, 100, offset=x-1)

        for size in (10, 100, 1000):
            for x in xrange(1, (50001 - size) / size):
                tools.query_columns(self, cursor, key, size, offset=x*size-1)
Exemplo n.º 10
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    def wide_row_test(self):
        """ Test wide row slices """
        cluster = self.cluster

        cluster.populate(3).start()
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 1)
        self.create_cf(session, 'cf')

        key = 'wide'

        for x in xrange(1, 5001):
            tools.insert_columns(self, session, key, 100, offset=x - 1)

        for size in (10, 100, 1000):
            for x in xrange(1, (50001 - size) / size):
                tools.query_columns(self, session, key, size, offset=x * size - 1)
Exemplo n.º 11
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    def short_read_delete_test(self):
        """ Test short reads ultimately leaving no columns alive [#4000] """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={"hinted_handoff_enabled": False}, batch_commitlog=True)

        cluster.populate(2).start()
        [node1, node2] = cluster.nodelist()
        time.sleep(0.5)

        cursor = self.patient_cql_connection(node1).cursor()
        self.create_ks(cursor, "ks", 3)
        self.create_cf(cursor, "cf", read_repair=0.0)
        # insert 2 columns in one row
        insert_columns(self, cursor, 0, 2)
        cursor.close()

        # Delete the row while first node is dead
        node1.flush()
        node1.stop(wait_other_notice=True)
        cursor = self.patient_cql_connection(node2, "ks").cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute("DELETE FROM cf WHERE key='k0'", consistency_level="ONE")
        else:
            cursor.execute("DELETE FROM cf USING CONSISTENCY ONE WHERE key=k0")
        cursor.close()
        node1.start(wait_other_notice=True)
        time.sleep(0.5)

        # Query first column
        cursor = self.patient_cql_connection(node1, "ks").cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute("SELECT c, v FROM cf WHERE key='k0' LIMIT 1", consistency_level="QUORUM")
            res = cursor.fetchone()
            assert cursor.rowcount == 0, res
        else:
            cursor.execute("SELECT FIRST 1 * FROM cf USING CONSISTENCY QUORUM WHERE key=k0")
            assert cursor.rowcount == 1
            res = cursor.fetchone()
            assert len(res) == 0, "Expecting no value, got %d (%s)" % (len(res), str(res))
Exemplo n.º 12
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    def short_read_reversed_test(self):
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={ 'hinted_handoff_enabled' : False}, batch_commitlog=True)

        cluster.populate(3).start()
        [node1, node2, node3] = cluster.nodelist()
        time.sleep(.5)

        cursor = self.cql_connection(node1).cursor()
        self.create_ks(cursor, 'ks', 3)
        self.create_cf(cursor, 'cf', read_repair=0.0)
        # insert 9 columns in one row
        insert_columns(self, cursor, 0, 9)
        cursor.close()

        # Deleting 3 last columns with a different node dead each time
        self.stop_delete_and_restart(1, 6)
        self.stop_delete_and_restart(2, 7)
        self.stop_delete_and_restart(3, 8)

        # Query 3 firsts columns
        cursor = self.cql_connection(node1, 'ks').cursor()
        if self.cluster.version() >= "1.2":
            cursor.execute('SELECT c, v FROM cf WHERE key=\'k0\' ORDER BY c DESC LIMIT 3', consistency_level="QUORUM")
            res = cursor.fetchall()
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (len(res), str(res))
            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                assert res[i][1] == 'value%d' % (5-i), 'Expecting value%d, got %s (%s)' % (5-i, res[i][1], str(res))
        else:
            cursor.execute('SELECT FIRST 3 REVERSED * FROM cf USING CONSISTENCY QUORUM WHERE key=k0')
            assert cursor.rowcount == 1
            res = cursor.fetchone()
            # the key is returned
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (len(res), str(res))
            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                assert res[i] == 'value%d' % (5-i), 'Expecting value%d, got %s (%s)' % (5-i, res[i], str(res))
    def short_read_reversed_test(self):
        """
        @jira_ticket CASSANDRA-9460
        """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfere with the test
        cluster.set_configuration_options(values={'hinted_handoff_enabled': False}, batch_commitlog=True)

        cluster.populate(3).start(wait_other_notice=True)
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 3)
        self.create_cf(session, 'cf', read_repair=0.0)

        # Repeat this test 10 times to make it more easy to spot a null pointer exception caused by a race, see CASSANDRA-9460
        for k in xrange(10):
            # insert 9 columns in one row
            insert_columns(self, session, 0, 9)

            # Deleting 3 last columns with a different node dead each time
            self.stop_delete_and_restart(1, 6)
            self.stop_delete_and_restart(2, 7)
            self.stop_delete_and_restart(3, 8)

            # Query 3 firsts columns
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement('SELECT c, v FROM cf WHERE key=\'k0\' ORDER BY c DESC LIMIT 3', consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert len(res) == 3, 'Expecting 3 values, got %d (%s)' % (len(res), str(res))
            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                assert res[i][1] == 'value%d' % (5 - i), 'Expecting value%d, got %s (%s)' % (5 - i, res[i][1], str(res))

            truncate_statement = SimpleStatement('TRUNCATE cf', consistency_level=ConsistencyLevel.QUORUM)
            session.execute(truncate_statement)
Exemplo n.º 14
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    def short_read_test(self):
        """
        @jira_ticket CASSANDRA-9460
        """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={'hinted_handoff_enabled': False})
        cluster.set_batch_commitlog(enabled=True)

        cluster.populate(3).start(wait_other_notice=True)
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 3)
        self.create_cf(session, 'cf', read_repair=0.0)

        normal_key = 'normal'
        reversed_key = 'reversed'

        # Repeat this test 10 times to make it more easy to spot a null pointer exception caused by a race, see CASSANDRA-9460
        for k in xrange(10):
            # insert 9 columns in two rows
            insert_columns(self, session, normal_key, 9)
            insert_columns(self, session, reversed_key, 9)

            # Delete 3 first columns (and 3 last columns, for the reversed version) with a different node dead each time
            for node, column_number_to_delete in zip(range(1, 4), range(3)):
                self.stop_node(node)
                self.delete(node, normal_key, column_number_to_delete)
                self.delete(node, reversed_key, 8 - column_number_to_delete)
                self.restart_node(node)

            # Query 3 firsts columns in normal order
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement(
                'SELECT c, v FROM cf WHERE key=\'k{}\' LIMIT 3'.format(normal_key),
                consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert_length_equal(res, 3)

            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                self.assertEqual('value{}'.format(i + 2), res[i - 1][1])

            # Query 3 firsts columns in reverse order
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement(
                'SELECT c, v FROM cf WHERE key=\'k{}\' ORDER BY c DESC LIMIT 3'.format(reversed_key),
                consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert_length_equal(res, 3)

            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                self.assertEqual('value{}'.format(5 - i), res[i][1])

            session.execute('TRUNCATE cf')
Exemplo n.º 15
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    def short_read_test(self):
        """
        @jira_ticket CASSANDRA-9460
        """
        cluster = self.cluster

        # Disable hinted handoff and set batch commit log so this doesn't
        # interfer with the test
        cluster.set_configuration_options(values={'hinted_handoff_enabled': False})
        cluster.set_batch_commitlog(enabled=True)

        cluster.populate(3).start(wait_other_notice=True)
        node1, node2, node3 = cluster.nodelist()

        session = self.patient_cql_connection(node1)
        self.create_ks(session, 'ks', 3)
        self.create_cf(session, 'cf', read_repair=0.0)

        normal_key = 'normal'
        reversed_key = 'reversed'

        # Repeat this test 10 times to make it more easy to spot a null pointer exception caused by a race, see CASSANDRA-9460
        for k in xrange(10):
            # insert 9 columns in two rows
            insert_columns(self, session, normal_key, 9)
            insert_columns(self, session, reversed_key, 9)

            # Delete 3 first columns (and 3 last columns, for the reversed version) with a different node dead each time
            for node, column_number_to_delete in zip(range(1, 4), range(3)):
                self.stop_node(node)
                self.delete(node, normal_key, column_number_to_delete)
                self.delete(node, reversed_key, 8 - column_number_to_delete)
                self.restart_node(node)

            # Query 3 firsts columns in normal order
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement(
                'SELECT c, v FROM cf WHERE key=\'k{}\' LIMIT 3'.format(normal_key),
                consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert_length_equal(res, 3)

            # value 0, 1 and 2 have been deleted
            for i in xrange(1, 4):
                self.assertEqual('value{}'.format(i + 2), res[i - 1][1])

            # Query 3 firsts columns in reverse order
            session = self.patient_cql_connection(node1, 'ks')
            query = SimpleStatement(
                'SELECT c, v FROM cf WHERE key=\'k{}\' ORDER BY c DESC LIMIT 3'.format(reversed_key),
                consistency_level=ConsistencyLevel.QUORUM)
            rows = list(session.execute(query))
            res = rows
            assert_length_equal(res, 3)

            # value 6, 7 and 8 have been deleted
            for i in xrange(0, 3):
                self.assertEqual('value{}'.format(5 - i), res[i][1])

            session.execute('TRUNCATE cf')