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

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

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

EMPTY

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.
PartitionRangeReadCommand	copyAsDigestQuery() Returns a copy of this command with isDigestQuery set to true.
static PartitionRangeReadCommand	create(boolean isForThrift, CFMetaData metadata, int nowInSec, ColumnFilter columnFilter, RowFilter rowFilter, DataLimits limits, DataRange dataRange)
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	isLimitedToOnePartition()
boolean	isNamesQuery()
boolean	isReversed() Whether the underlying ClusteringIndexFilter is reversed or not.
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.
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	selectsFullPartition() Checks if this ReadQuery selects full partitions, that is it has no filtering on clustering or regular columns.
boolean	selectsKey(DecoratedKey key)
protected void	serializeSelection(DataOutputPlus out, int version)
java.lang.String	toString()
PartitionRangeReadCommand	withUpdatedDataRange(DataRange newDataRange)
ReadCommand	withUpdatedLimit(DataLimits newLimits) Creates a new ReadCommand instance with new limits.
PartitionRangeReadCommand	withUpdatedLimitsAndDataRange(DataLimits newLimits, DataRange newDataRange)

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

columnFilter, createResponse, digestVersion, executeInternal, executeLocally, executionController, getIndex, indexMetadata, isDigestQuery, isForThrift, limits, maybeValidateIndex, metadata, name, nowInSec, rowFilter, setDigestVersion, 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

Method Detail

create

public static PartitionRangeReadCommand create(boolean isForThrift,
                                               CFMetaData metadata,
                                               int nowInSec,
                                               ColumnFilter columnFilter,
                                               RowFilter rowFilter,
                                               DataLimits limits,
                                               DataRange dataRange)

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.

copyAsDigestQuery

public PartitionRangeReadCommand copyAsDigestQuery()

Description copied from class: ReadCommand

Returns a copy of this command with isDigestQuery set to true.

Specified by:

copyAsDigestQuery in class ReadCommand

withUpdatedLimit

public ReadCommand 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

withUpdatedDataRange

public PartitionRangeReadCommand withUpdatedDataRange(DataRange newDataRange)

withUpdatedLimitsAndDataRange

public PartitionRangeReadCommand withUpdatedLimitsAndDataRange(DataLimits newLimits,
                                                               DataRange newDataRange)

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.

isReversed

public boolean isReversed()

Description copied from class: ReadCommand

Whether the underlying ClusteringIndexFilter is reversed or not.

Specified by:

isReversed in class ReadCommand

Returns:

whether the underlying ClusteringIndexFilter is reversed or not.

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

public 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.

selectsFullPartition

public boolean selectsFullPartition()

Description copied from interface: ReadQuery

Checks if this ReadQuery selects full partitions, that is it has no filtering on clustering or regular columns.

Returns:

true if this ReadQuery selects full partitions, false otherwise.

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

isLimitedToOnePartition

public boolean isLimitedToOnePartition()

Specified by:

isLimitedToOnePartition in class ReadCommand