Package org.apache.druid.segment

Class CursorBuildSpec

java.lang.Object

org.apache.druid.segment.CursorBuildSpec

public class CursorBuildSpec
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CursorBuildSpec.CursorBuildSpecBuilder

Field Summary

Fields

Modifier and Type	Field	Description
static CursorBuildSpec	FULL_SCAN

Constructor Summary

Constructors

Constructor	Description
CursorBuildSpec(Filter filter, org.joda.time.Interval interval, Set<String> physicalColumns, VirtualColumns virtualColumns, List<String> groupingColumns, List<AggregatorFactory> aggregators, List<OrderBy> preferredOrdering, QueryContext queryContext, QueryMetrics<?> queryMetrics)

Method Summary

Modifier and Type	Method	Description
static CursorBuildSpec.CursorBuildSpecBuilder	builder()
static CursorBuildSpec.CursorBuildSpecBuilder	builder(CursorBuildSpec spec)
List<AggregatorFactory>	getAggregators()	Any AggregatorFactory which will be used by a query engine for the CursorHolder, useful to assist in determining if CursorHolder.canVectorize(), as well as specializing the Cursor or VectorCursor if any pre-aggregated data is available.
Filter	getFilter()	Filter to supply to the CursorHolder.
List<String>	getGroupingColumns()	Any columns which will be used for grouping by a query engine for the CursorHolder, useful for specializing the Cursor or VectorCursor if any pre-aggregated data is available.
org.joda.time.Interval	getInterval()	Interval filter to supply to the CursorHolder.
Set<String>	getPhysicalColumns()	Set of physical columns required from a cursor.
List<OrderBy>	getPreferredOrdering()	List of all OrderBy columns which a query engine will use to sort its results to supply to the CursorHolder, which can allow optimization of the provided Cursor or VectorCursor if data matching the preferred ordering is available.
QueryContext	getQueryContext()	QueryContext for the CursorHolder to provide a mechanism to push various data into Cursor and VectorCursor such as QueryContexts.VECTORIZE_KEY and QueryContexts.VECTOR_SIZE_KEY
QueryMetrics<?>	getQueryMetrics()	QueryMetrics to use for measuring things involved with Cursor and VectorCursor creation.
VirtualColumns	getVirtualColumns()	Any VirtualColumns which are used by a query engine to assist in determining if CursorHolder.canVectorize()
boolean	isAggregate()	Returns true if getGroupingColumns() is not null or empty and/or getAggregators() is not null or empty.
boolean	isCompatibleOrdering(List<OrderBy> ordering)	Returns true if the supplied ordering matches getPreferredOrdering(), meaning that the supplied ordering has everything which is in the preferred ordering in the same direction and order.

Methods inherited from class java.lang.Object

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

Field Detail

FULL_SCAN

public static final CursorBuildSpec FULL_SCAN

Constructor Detail

CursorBuildSpec

public CursorBuildSpec(@Nullable
                       Filter filter,
                       org.joda.time.Interval interval,
                       @Nullable
                       Set<String> physicalColumns,
                       VirtualColumns virtualColumns,
                       @Nullable
                       List<String> groupingColumns,
                       @Nullable
                       List<AggregatorFactory> aggregators,
                       List<OrderBy> preferredOrdering,
                       QueryContext queryContext,
                       @Nullable
                       QueryMetrics<?> queryMetrics)

Method Detail

builder

public static CursorBuildSpec.CursorBuildSpecBuilder builder()

builder

public static CursorBuildSpec.CursorBuildSpecBuilder builder(CursorBuildSpec spec)

getFilter

@Nullable
public Filter getFilter()

Filter to supply to the CursorHolder. Only rows which match will be available through the selectors created from the Cursor or VectorCursor

getInterval

public org.joda.time.Interval getInterval()

Interval filter to supply to the CursorHolder. Only rows whose timestamps fall within this range will be available through the selectors created from the Cursor or VectorCursor

getPhysicalColumns

@Nullable
public Set<String> getPhysicalColumns()

Set of physical columns required from a cursor. If null, and groupingColumns is null or empty and aggregators is null or empty, then a CursorHolder must assume that ALL columns are required

getVirtualColumns

public VirtualColumns getVirtualColumns()

Any VirtualColumns which are used by a query engine to assist in determining if CursorHolder.canVectorize()

getGroupingColumns

@Nullable
public List<String> getGroupingColumns()

Any columns which will be used for grouping by a query engine for the CursorHolder, useful for specializing the Cursor or VectorCursor if any pre-aggregated data is available.

getAggregators

@Nullable
public List<AggregatorFactory> getAggregators()

Any AggregatorFactory which will be used by a query engine for the CursorHolder, useful to assist in determining if CursorHolder.canVectorize(), as well as specializing the Cursor or VectorCursor if any pre-aggregated data is available.

getPreferredOrdering

public List<OrderBy> getPreferredOrdering()

List of all OrderBy columns which a query engine will use to sort its results to supply to the CursorHolder, which can allow optimization of the provided Cursor or VectorCursor if data matching the preferred ordering is available.

If not specified, the cursor will advance in the native order of the underlying data.

getQueryContext

public QueryContext getQueryContext()

QueryContext for the CursorHolder to provide a mechanism to push various data into Cursor and VectorCursor such as QueryContexts.VECTORIZE_KEY and QueryContexts.VECTOR_SIZE_KEY

getQueryMetrics

@Nullable
public QueryMetrics<?> getQueryMetrics()

QueryMetrics to use for measuring things involved with Cursor and VectorCursor creation.

isAggregate

public boolean isAggregate()

Returns true if getGroupingColumns() is not null or empty and/or getAggregators() is not null or empty. This method is useful for quickly checking if it is worth considering if a CursorFactory should attempt to produce a CursorHolder that is CursorHolder.isPreAggregated() to satisfy the build spec.

isCompatibleOrdering

public boolean isCompatibleOrdering(List<OrderBy> ordering)

Returns true if the supplied ordering matches getPreferredOrdering(), meaning that the supplied ordering has everything which is in the preferred ordering in the same direction and order. The supplied ordering may have additional columns beyond the preferred ordering and still satisify this method.