Package org.apache.cassandra.db.rows

Class UnfilteredRowIteratorWithLowerBound

java.lang.Object

org.apache.cassandra.utils.AbstractIterator<Unfiltered>

org.apache.cassandra.db.rows.LazilyInitializedUnfilteredRowIterator

org.apache.cassandra.db.rows.UnfilteredRowIteratorWithLowerBound

All Implemented Interfaces:

com.google.common.collect.PeekingIterator<Unfiltered>, AutoCloseable, Iterator<Unfiltered>, BaseRowIterator<Unfiltered>, UnfilteredRowIterator, CloseableIterator<Unfiltered>, IteratorWithLowerBound<Unfiltered>

public class UnfilteredRowIteratorWithLowerBound
extends LazilyInitializedUnfilteredRowIterator
implements IteratorWithLowerBound<Unfiltered>

An unfiltered row iterator with a lower bound retrieved from either the global sstable statistics or the row index lower bounds (if available in the cache). Before initializing the sstable unfiltered row iterator, we return an empty row with the clustering set to the lower bound. The empty row will be filtered out and the result is that if we don't need to access this sstable, i.e. due to the LIMIT conditon, then we will not. See CASSANDRA-8180 for examples of why this is useful.

Constructor Summary

Constructors

Constructor	Description
UnfilteredRowIteratorWithLowerBound(DecoratedKey partitionKey, SSTableReader sstable, ClusteringIndexFilter filter, ColumnFilter selectedColumns, SSTableReadsListener listener)
UnfilteredRowIteratorWithLowerBound(DecoratedKey partitionKey, SSTableReader sstable, Slices slices, boolean isReverseOrder, ColumnFilter selectedColumns, SSTableReadsListener listener)

Method Summary

Modifier and Type	Method	Description
static void	assertBoundSize(ClusteringPrefix<?> lowerBound, SSTable sstable)
RegularAndStaticColumns	columns()	A subset of the columns for the (static and regular) rows returned by this iterator.
protected Unfiltered	computeNext()
protected UnfilteredRowIterator	initializeIterator()
boolean	isReverseOrder()	Whether or not the rows returned by this iterator are in reversed clustering order.
Unfiltered	lowerBound()
TableMetadata	metadata()	The metadata for the table this iterator on.
DeletionTime	partitionLevelDeletion()	The partition level deletion for the partition this iterate over.
Row	staticRow()	The static part corresponding to this partition (this can be an empty row but cannot be null).
EncodingStats	stats()	Return "statistics" about what is returned by this iterator.

Methods inherited from class org.apache.cassandra.db.rows.LazilyInitializedUnfilteredRowIterator

close, isOpen, maybeInit, partitionKey

Methods inherited from class org.apache.cassandra.utils.AbstractIterator

endOfData, hasNext, next, peek, remove

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext

Methods inherited from interface org.apache.cassandra.db.rows.UnfilteredRowIterator

isEmpty

Constructor Details

UnfilteredRowIteratorWithLowerBound

public UnfilteredRowIteratorWithLowerBound(DecoratedKey partitionKey,
 SSTableReader sstable,
 ClusteringIndexFilter filter,
 ColumnFilter selectedColumns,
 SSTableReadsListener listener)

UnfilteredRowIteratorWithLowerBound

public UnfilteredRowIteratorWithLowerBound(DecoratedKey partitionKey,
 SSTableReader sstable,
 Slices slices,
 boolean isReverseOrder,
 ColumnFilter selectedColumns,
 SSTableReadsListener listener)

Method Details

lowerBound

public Unfiltered lowerBound()

Specified by:

lowerBound in interface IteratorWithLowerBound<Unfiltered>

initializeIterator

protected UnfilteredRowIterator initializeIterator()

Specified by:

initializeIterator in class LazilyInitializedUnfilteredRowIterator

computeNext

protected Unfiltered computeNext()

Overrides:

computeNext in class LazilyInitializedUnfilteredRowIterator

metadata

public TableMetadata metadata()

Description copied from interface: BaseRowIterator

The metadata for the table this iterator on.

Specified by:

metadata in interface BaseRowIterator<Unfiltered>

Overrides:

metadata in class LazilyInitializedUnfilteredRowIterator

isReverseOrder

public boolean isReverseOrder()

Description copied from interface: BaseRowIterator

Whether or not the rows returned by this iterator are in reversed clustering order.

Specified by:

isReverseOrder in interface BaseRowIterator<Unfiltered>

Overrides:

isReverseOrder in class LazilyInitializedUnfilteredRowIterator

columns

public RegularAndStaticColumns columns()

Description copied from interface: BaseRowIterator

A subset of the columns for the (static and regular) rows returned by this iterator. Every row returned by this iterator must guarantee that it has only those columns.

Specified by:

columns in interface BaseRowIterator<Unfiltered>

Overrides:

columns in class LazilyInitializedUnfilteredRowIterator

stats

public EncodingStats stats()

Description copied from interface: UnfilteredRowIterator

Return "statistics" about what is returned by this iterator. Those are used for performance reasons (for delta-encoding for instance) and code should not expect those to be exact.

Specified by:

stats in interface UnfilteredRowIterator

Overrides:

stats in class LazilyInitializedUnfilteredRowIterator

partitionLevelDeletion

public DeletionTime partitionLevelDeletion()

Description copied from interface: UnfilteredRowIterator

The partition level deletion for the partition this iterate over.

Specified by:

partitionLevelDeletion in interface UnfilteredRowIterator

Overrides:

partitionLevelDeletion in class LazilyInitializedUnfilteredRowIterator

staticRow

public Row staticRow()

Description copied from interface: BaseRowIterator

The static part corresponding to this partition (this can be an empty row but cannot be null).

Specified by:

staticRow in interface BaseRowIterator<Unfiltered>

Overrides:

staticRow in class LazilyInitializedUnfilteredRowIterator

assertBoundSize

public static void assertBoundSize(ClusteringPrefix<?> lowerBound,
 SSTable sstable)