• DataStax Enterprise C# Driver API Documentation

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    • Dse
      • AggregateMetadata
      • AlreadyExistsException
      • AtomicMonotonicTimestampGenerator
      • AtomicMonotonicWinApiTimestampGenerator
      • AuthenticationException
      • BatchStatement
      • BatchType
      • BigIntegerTypeAdapter
      • BoundStatement
      • Builder
      • BusyPoolException
      • CassandraConnectionStringBuilder
      • ClientOptions
      • Cluster
      • ColumnDesc
      • ColumnTypeCode
      • CompressionType
      • Configuration
      • ConsistencyLevel
      • ConstantReconnectionPolicy
      • ConstantSpeculativeExecutionPolicy
      • CqlColumn
      • CustomColumnInfo
      • DataCollectionMetadata
      • DataCollectionMetadata.SortOrder
      • DCAwareRoundRobinPolicy
      • DecimalTypeAdapter
      • DefaultRetryPolicy
      • Diagnostics
      • DowngradingConsistencyRetryPolicy
      • DriverException
      • DriverInternalError
      • DseCluster
      • DseClusterBuilder
      • DseConfiguration
      • DseLoadBalancingPolicy
      • Duration
      • DynamicCompositeTypeAdapter
      • EC2MultiRegionTranslator
      • ExecutionException
      • ExecutionInfo
      • ExponentialReconnectionPolicy
      • Extensions
      • FallthroughRetryPolicy
      • FixedReconnectionPolicy
      • FunctionFailureException
      • FunctionMetadata
      • Host
      • HostDistance
      • HostsEventArgs
      • HostsEventArgs.Kind
      • HostsEventHandler
      • IAddressTranslator
      • IAuthenticator
      • IAuthProvider
      • IAuthProviderNamed
      • ICluster
      • IColumnInfo
      • IdempotenceAwareRetryPolicy
      • IDseCluster
      • IDseSession
      • IExecutionProfile
      • IExecutionProfileBuilder
      • IExecutionProfileOptions
      • IExtendedRetryPolicy
      • IFrameCompressor
      • IInitializer
      • ILoadBalancingPolicy
      • IndexMetadata
      • IndexMetadata.IndexKind
      • InvalidConfigurationInQueryException
      • InvalidQueryException
      • InvalidTypeException
      • IReconnectionPolicy
      • IReconnectionSchedule
      • IRetryPolicy
      • IsBootstrappingException
      • ISession
      • ISessionState
      • ISpeculativeExecutionPlan
      • ISpeculativeExecutionPolicy
      • IStatement
      • ITimestampGenerator
      • ITypeAdapter
      • KeyspaceMetadata
      • KeyType
      • ListColumnInfo
      • LocalDate
      • LocalTime
      • Logger
      • LoggingRetryPolicy
      • MapColumnInfo
      • MaterializedViewMetadata
      • Metadata
      • MetadataSyncOptions
      • MetricsExtensions
      • MonitorReportingOptions
      • NoHostAvailableException
      • NoneAuthProvider
      • NoSpeculativeExecutionPolicy
      • NullTypeAdapter
      • OperationTimedOutException
      • OverloadedException
      • PlainTextAuthProvider
      • Policies
      • PoolingOptions
      • PreparedQueryNotFoundException
      • PreparedStatement
      • PreparedStatementIdMismatchException
      • ProtocolErrorException
      • ProtocolOptions
      • ProtocolVersion
      • QueryExecutionException
      • QueryOptions
      • QueryProtocolOptions
      • QueryProtocolOptions.QueryFlags
      • QueryTimeoutException
      • QueryTrace
      • QueryTrace.Event
      • QueryValidationException
      • ReadFailureException
      • ReadTimeoutException
      • RegularStatement
      • ReplicationStrategies
      • RequestInvalidException
      • RetryDecision
      • RetryDecision.RetryDecisionType
      • RetryLoadBalancingPolicy
      • RetryLoadBalancingPolicyEventArgs
      • RoundRobinPolicy
      • RoutingKey
      • Row
      • RowSet
      • RowSetMetadata
      • SchemaChangedEventArgs
      • SchemaChangedEventArgs.Kind
      • SchemaChangedEventHandler
      • ServerErrorException
      • Session
      • SetColumnInfo
      • SimpleStatement
      • SocketOptions
      • SSLOptions
      • Statement
      • SyntaxError
      • TableColumn
      • TableMetadata
      • TableOptions
      • TimeUuid
      • TokenAwarePolicy
      • ToManyConnectionsPerHost
      • TraceRetrievalException
      • TruncateException
      • TupleColumnInfo
      • TypeAdapters
      • UdtColumnInfo
      • UdtMap
      • UdtMap<T>
      • UdtMappingDefinitions
      • UnauthorizedException
      • UnavailableException
      • Unset
      • WriteFailureException
      • WriteTimeoutException
    • Dse.AppMetrics
      • DriverAppMetricsOptions
    • Dse.AppMetrics.MetricTypes
      • IAppMetricsCounter
      • IAppMetricsGauge
      • IAppMetricsMeter
      • IAppMetricsMetric
      • IAppMetricsTimer
    • Dse.AppMetrics.MetricValues
      • IAppMetricsHistogramValue
      • IAppMetricsMeterValue
      • IAppMetricsMetricWithValue<T>
      • IAppMetricsTimerValue
    • Dse.Auth
      • DseGssapiAuthProvider
      • DsePlainTextAuthProvider
    • Dse.Auth.Sspi
      • SspiException
    • Dse.Data
      • CqlBatchTransaction
      • CqlCommand
      • CqlConnection
      • CqlDataAdapter
      • CqlParameter
      • CqlParameterCollection
      • CqlProviderFactory
      • CqlReader
    • Dse.Data.Linq
      • AllowFilteringAttribute
      • Batch
      • ClusteringKeyAttribute
      • ColumnAttribute
      • CompactStorageAttribute
      • CounterAttribute
      • CqlArgumentException
      • CqlCommand
      • CqlConditionalCommand<TEntity>
      • CqlDelete
      • CqlFunction
      • CqlInsert<TEntity>
      • CqlLinqNotSupportedException
      • CqlOperator
      • CqlQuery<TEntity>
      • CqlQueryBase<TEntity>
      • CqlQueryExtensions
      • CqlQuerySingleElement<TEntity>
      • CqlScalar<TEntity>
      • CqlToken
      • CqlUpdate
      • IgnoreAttribute
      • ITable
      • PartitionKeyAttribute
      • SecondaryIndexAttribute
      • SessionExtensions
      • StaticColumnAttribute
      • Table<TEntity>
      • TableAttribute
      • TableType
    • Dse.Geometry
      • GeometryBase
      • LineString
      • Point
      • Polygon
    • Dse.Graph
      • Edge
      • Element
      • GraphNode
      • GraphOptions
      • GraphResultSet
      • GraphStatement
      • IEdge
      • IElement
      • IGraphNode
      • IGraphStatement
      • IPath
      • IProperty
      • IVertex
      • IVertexProperty
      • Path
      • SimpleGraphStatement
      • Vertex
    • Dse.Mapping
      • AppliedInfo<T>
      • ColumnMap
      • Cql
      • CqlQueryOptions
      • IColumnDefinition
      • ICqlBatch
      • ICqlQueryAsyncClient
      • ICqlQueryClient
      • ICqlWriteAsyncClient
      • ICqlWriteClient
      • IMapper
      • IPage<T>
      • ITypeDefinition
      • Map<TPoco>
      • Mapper
      • MappingConfiguration
      • Mappings
      • SortOrder
    • Dse.Mapping.Attributes
      • ClusteringKeyAttribute
      • ColumnAttribute
      • CounterAttribute
      • FrozenAttribute
      • FrozenKeyAttribute
      • FrozenValueAttribute
      • IgnoreAttribute
      • PartitionKeyAttribute
      • SecondaryIndexAttribute
      • StaticColumnAttribute
      • TableAttribute
    • Dse.Mapping.TypeConversion
      • DefaultTypeConverter
      • EnumStringMapper<T>
      • NullableEnumStringMapper<T>
      • TypeConverter
    • Dse.Mapping.Utils
      • MemberInfoExtensions
    • Dse.Metrics
      • DriverMetricsOptions
      • IDriverMetrics
      • IMetric
      • IMetricsRegistry<TMetric>
      • NodeMetric
      • NodeMetric.Counters
      • NodeMetric.Gauges
      • NodeMetric.Meters
      • NodeMetric.Timers
      • SessionMetric
      • SessionMetric.Counters
      • SessionMetric.Gauges
      • SessionMetric.Meters
      • SessionMetric.Timers
    • Dse.Metrics.Abstractions
      • IDriverCounter
      • IDriverGauge
      • IDriverMeter
      • IDriverMetric
      • IDriverMetricsProvider
      • IDriverTimer
    • Dse.Search
      • DateRange
      • DateRangeBound
      • DateRangePrecision
    • Dse.Serialization
      • CustomTypeSerializer<T>
      • TypeSerializer
      • TypeSerializer<T>
      • TypeSerializerDefinitions
      • UdtSerializer

    Class Unset

    The Unset class represents a unspecified value.

    In Cassandra 2.2 and above, when executing a UPDATE or INSERT query, a parameter can be unset. Designed to avoid tombstones, setting a parameter value to Unset will make Cassandra to ignore it.

    In some cases, we might be inserting rows using null for values that are not specified, and even though our intention is to leave the value empty, Cassandra will represent it as a tombstone causing an unnecessary overhead. To avoid tombstones, in previous versions of Cassandra, you can use different query combinations only containing the fields that have a value.

    The Unset type is a singleton class, which means only one Unset object exists. The Unset.Value member represents the sole Unset object.

    Inheritance
    System.Object
    Unset
    Inherited Members
    System.Object.Equals(System.Object)
    System.Object.Equals(System.Object, System.Object)
    System.Object.GetHashCode()
    System.Object.GetType()
    System.Object.MemberwiseClone()
    System.Object.ReferenceEquals(System.Object, System.Object)
    System.Object.ToString()
    Namespace: Dse
    Assembly: Dse.dll
    Syntax
    public sealed class Unset

    Fields

    Value

    Represents the sole instance of the Unset class.

    Declaration
    public static readonly Unset Value
    Field Value
    Type Description
    Unset
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