org.apache.cassandra.db

Class PartitionRangeReadCommand

java.lang.Object

org.apache.cassandra.db.monitoring.MonitorableImpl

org.apache.cassandra.db.ReadCommand

org.apache.cassandra.db.PartitionRangeReadCommand

All Implemented Interfaces:

Monitorable, ReadQuery

public class PartitionRangeReadCommand
extends ReadCommand

A read command that selects a (part of a) range of partitions.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.cassandra.db.ReadCommand

ReadCommand.CheckForAbort, ReadCommand.Kind, ReadCommand.SelectionDeserializer

Field Summary

Fields

Modifier and Type	Field and Description
protected static ReadCommand.SelectionDeserializer	selectionDeserializer

Fields inherited from class org.apache.cassandra.db.ReadCommand

index, legacyPagedRangeCommandSerializer, legacyRangeSliceCommandSerializer, legacyReadCommandSerializer, logger, pagedRangeSerializer, rangeSliceSerializer, readSerializer, serializer

Fields inherited from interface org.apache.cassandra.db.ReadQuery

EMPTY

Constructor Summary

Constructors

Constructor and Description
PartitionRangeReadCommand(boolean isDigest, int digestVersion, boolean isForThrift, CFMetaData metadata, int nowInSec, ColumnFilter columnFilter, RowFilter rowFilter, DataLimits limits, DataRange dataRange, java.util.Optional<IndexMetadata> index)
PartitionRangeReadCommand(CFMetaData metadata, int nowInSec, ColumnFilter columnFilter, RowFilter rowFilter, DataLimits limits, DataRange dataRange, java.util.Optional<IndexMetadata> index)

Method Summary

Modifier and Type	Method and Description
static PartitionRangeReadCommand	allDataRead(CFMetaData metadata, int nowInSec) Creates a new read command that query all the data in the table.
protected void	appendCQLWhereClause(java.lang.StringBuilder sb)
ClusteringIndexFilter	clusteringIndexFilter(DecoratedKey key) The clustering index filter this command to use for the provided key.
PartitionRangeReadCommand	copy() Returns a copy of this command.
MessageOut<ReadCommand>	createMessage(int version) Creates a message for this command.
DataRange	dataRange()
PartitionIterator	execute(ConsistencyLevel consistency, ClientState clientState, long queryStartNanoTime) Executes the query at the provided consistency level.
PartitionRangeReadCommand	forSubRange(AbstractBounds<PartitionPosition> range, boolean isRangeContinuation) Returns an equivalent command but that only queries data within the provided range.
QueryPager	getPager(PagingState pagingState, ProtocolVersion protocolVersion) Returns a pager for the query.
long	getTimeout() The configured timeout for this command.
boolean	isNamesQuery()
protected int	oldestUnrepairedTombstone()
PartitionIterator	postReconciliationProcessing(PartitionIterator result) Allow to post-process the result of the query after it has been reconciled on the coordinator but before it is passed to the CQL layer to return the ResultSet.
protected UnfilteredPartitionIterator	queryStorage(ColumnFamilyStore cfs, ReadExecutionController executionController)
protected void	recordLatency(TableMetrics metric, long latencyNanos)
protected long	selectionSerializedSize(int version)
boolean	selectsClustering(DecoratedKey key, Clustering clustering)
boolean	selectsKey(DecoratedKey key)
protected void	serializeSelection(DataOutputPlus out, int version)
java.lang.String	toString()
PartitionRangeReadCommand	withUpdatedLimit(DataLimits newLimits) Creates a new ReadCommand instance with new limits.

Methods inherited from class org.apache.cassandra.db.ReadCommand

columnFilter, createResponse, digestVersion, executeInternal, executeLocally, executionController, getIndex, indexSerializedSize, isDigestQuery, isForThrift, limits, maybeValidateIndex, metadata, name, nowInSec, rowFilter, setDigestVersion, setIsDigestQuery, toCQLString, withoutPurgeableTombstones, withStateTracking

Methods inherited from class org.apache.cassandra.db.monitoring.MonitorableImpl

abort, complete, constructionTime, isAborted, isCompleted, isCrossNode, isInProgress, isSlow, setMonitoringTime, slowTimeout, timeout

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

selectionDeserializer

protected static final ReadCommand.SelectionDeserializer selectionDeserializer

Constructor Detail

PartitionRangeReadCommand

public PartitionRangeReadCommand(boolean isDigest,
                                 int digestVersion,
                                 boolean isForThrift,
                                 CFMetaData metadata,
                                 int nowInSec,
                                 ColumnFilter columnFilter,
                                 RowFilter rowFilter,
                                 DataLimits limits,
                                 DataRange dataRange,
                                 java.util.Optional<IndexMetadata> index)

PartitionRangeReadCommand

public PartitionRangeReadCommand(CFMetaData metadata,
                                 int nowInSec,
                                 ColumnFilter columnFilter,
                                 RowFilter rowFilter,
                                 DataLimits limits,
                                 DataRange dataRange,
                                 java.util.Optional<IndexMetadata> index)

Method Detail

allDataRead

public static PartitionRangeReadCommand allDataRead(CFMetaData metadata,
                                                    int nowInSec)

Creates a new read command that query all the data in the table.

Parameters:

metadata - the table to query.

nowInSec - the time in seconds to use are "now" for this query.

Returns:

a newly created read command that queries everything in the table.

dataRange

public DataRange dataRange()

clusteringIndexFilter

public ClusteringIndexFilter clusteringIndexFilter(DecoratedKey key)

Description copied from class: ReadCommand

The clustering index filter this command to use for the provided key.

Note that that method should only be called on a key actually queried by this command and in practice, this will almost always return the same filter, but for the sake of paging, the filter on the first key of a range command might be slightly different.

Specified by:

clusteringIndexFilter in class ReadCommand

Parameters:

key - a partition key queried by this command.

Returns:

the ClusteringIndexFilter to use for the partition of key key.

isNamesQuery

public boolean isNamesQuery()

forSubRange

public PartitionRangeReadCommand forSubRange(AbstractBounds<PartitionPosition> range,
                                             boolean isRangeContinuation)

Returns an equivalent command but that only queries data within the provided range.

Parameters:

range - the sub-range to restrict the command to. This method assumes that this is a proper sub-range of the command this is applied to.

isRangeContinuation - whether range is a direct continuation of whatever previous range we have queried. This matters for the DataLimits that may contain states when we do paging and in the context of parallel queries: that state only make sense if the range queried is indeed the follow-up of whatever range we've previously query (that yield said state). In practice this means that ranges for which isRangeContinuation is false may have to be slightly pessimistic when counting data and may include a little bit than necessary, and this should be dealt with post-query (in the case of StorageProxy.getRangeSlice(), which uses this method for replica queries, this is dealt with by re-counting results on the coordinator). Note that if this is the first range we queried, then the DataLimits will have not state and the value of this parameter doesn't matter.

copy

public PartitionRangeReadCommand copy()

Description copied from class: ReadCommand

Returns a copy of this command.

Specified by:

copy in class ReadCommand

Returns:

a copy of this command.

withUpdatedLimit

public PartitionRangeReadCommand withUpdatedLimit(DataLimits newLimits)

Description copied from class: ReadCommand

Creates a new ReadCommand instance with new limits.

Specified by:

withUpdatedLimit in class ReadCommand

Parameters:

newLimits - the new limits

Returns:

a new ReadCommand with the updated limits

getTimeout

public long getTimeout()

Description copied from class: ReadCommand

The configured timeout for this command.

Specified by:

getTimeout in class ReadCommand

Returns:

the configured timeout for this command.

selectsKey

public boolean selectsKey(DecoratedKey key)

Returns:

true if the read query would select the given key, including checks against the row filter, if checkRowFilter is true

selectsClustering

public boolean selectsClustering(DecoratedKey key,
                                 Clustering clustering)

Returns:

true if the read query would select the given clustering, including checks against the row filter, if checkRowFilter is true

execute

public PartitionIterator execute(ConsistencyLevel consistency,
                                 ClientState clientState,
                                 long queryStartNanoTime)
                          throws RequestExecutionException

Description copied from interface: ReadQuery

Executes the query at the provided consistency level.

Parameters:

consistency - the consistency level to achieve for the query.

clientState - the ClientState for the query. In practice, this can be null unless consistency is a serial consistency.

Returns:

the result of the query.

Throws:

RequestExecutionException

getPager

public QueryPager getPager(PagingState pagingState,
                           ProtocolVersion protocolVersion)

Description copied from interface: ReadQuery

Returns a pager for the query.

Parameters:

pagingState - the PagingState to start from if this is a paging continuation. This can be null if this is the start of paging.

protocolVersion - the protocol version to use for the paging state of that pager.

Returns:

a pager for the query.

recordLatency

protected void recordLatency(TableMetrics metric,
                             long latencyNanos)

Specified by:

recordLatency in class ReadCommand

queryStorage

protected UnfilteredPartitionIterator queryStorage(ColumnFamilyStore cfs,
                                                   ReadExecutionController executionController)

Specified by:

queryStorage in class ReadCommand

oldestUnrepairedTombstone

protected int oldestUnrepairedTombstone()

Specified by:

oldestUnrepairedTombstone in class ReadCommand

createMessage

public MessageOut<ReadCommand> createMessage(int version)

Description copied from class: ReadCommand

Creates a message for this command.

Specified by:

createMessage in class ReadCommand

appendCQLWhereClause

protected void appendCQLWhereClause(java.lang.StringBuilder sb)

Specified by:

appendCQLWhereClause in class ReadCommand

postReconciliationProcessing

public PartitionIterator postReconciliationProcessing(PartitionIterator result)

Allow to post-process the result of the query after it has been reconciled on the coordinator but before it is passed to the CQL layer to return the ResultSet. See CASSANDRA-8717 for why this exists.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

serializeSelection

protected void serializeSelection(DataOutputPlus out,
                                  int version)
                           throws java.io.IOException

Specified by:

serializeSelection in class ReadCommand

Throws:

java.io.IOException

selectionSerializedSize

protected long selectionSerializedSize(int version)

Specified by:

selectionSerializedSize in class ReadCommand