org.apache.druid.query.scan

Class ScanQuery

java.lang.Object

org.apache.druid.query.BaseQuery<ScanResultValue>

org.apache.druid.query.scan.ScanQuery

All Implemented Interfaces:

Query<ScanResultValue>

public class ScanQuery
extends BaseQuery<ScanResultValue>

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ScanQuery.Order
static class	ScanQuery.ResultFormat

Field Summary

Fields

Modifier and Type	Field and Description
static String	CTX_KEY_OUTERMOST This context flag corresponds to whether the query is running on the "outermost" process (i.e.

Fields inherited from class org.apache.druid.query.BaseQuery

QUERY_ID, SQL_QUERY_ID, SUB_QUERY_ID

Fields inherited from interface org.apache.druid.query.Query

DATASOURCE_METADATA, GROUP_BY, SCAN, SEARCH, SEGMENT_METADATA, SELECT, TIME_BOUNDARY, TIMESERIES, TOPN

Constructor Summary

Constructors

Constructor and Description
ScanQuery(DataSource dataSource, QuerySegmentSpec querySegmentSpec, VirtualColumns virtualColumns, ScanQuery.ResultFormat resultFormat, int batchSize, long scanRowsOffset, long scanRowsLimit, ScanQuery.Order order, DimFilter dimFilter, List<String> columns, Boolean legacy, Map<String,Object> context)

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object o)
int	getBatchSize()
List<String>	getColumns()
DimFilter	getFilter()
Integer	getMaxRowsQueuedForOrdering()
Integer	getMaxSegmentPartitionsOrderedInMemory()
ScanQuery.Order	getOrder()
Set<String>	getRequiredColumns() Returns the set of columns that this query will need to access out of its datasource.
ScanQuery.ResultFormat	getResultFormat()
com.google.common.collect.Ordering<ScanResultValue>	getResultOrdering() Default implementation of Query.getResultOrdering() that uses Ordering.natural().
long	getScanRowsLimit() Limit for this query; behaves like SQL "LIMIT".
long	getScanRowsOffset() Offset for this query; behaves like SQL "OFFSET".
String	getType()
VirtualColumns	getVirtualColumns()
boolean	hasFilters()
int	hashCode()
Boolean	isLegacy() Compatibility mode with the legacy scan-query extension.
boolean	isLimited() Returns whether this query is limited or not.
String	toString()
Query<ScanResultValue>	withDataSource(DataSource dataSource)
ScanQuery	withLimit(long newLimit)
ScanQuery	withNonNullLegacy(ScanQueryConfig scanQueryConfig)
ScanQuery	withOffset(long newOffset)
Query<ScanResultValue>	withOverriddenContext(Map<String,Object> contextOverrides)
Query<ScanResultValue>	withQuerySegmentSpec(QuerySegmentSpec querySegmentSpec) Returns a new query, identical to this one, but with a different associated QuerySegmentSpec.

Methods inherited from class org.apache.druid.query.BaseQuery

checkInterrupted, computeOverriddenContext, computeOverridenContext, getContext, getContextBoolean, getContextValue, getContextValue, getDataSource, getDuration, getGranularity, getId, getIntervals, getQuerySegmentSpec, getQuerySegmentSpecForLookUp, getRunner, getSqlQueryId, getSubQueryId, getTimezone, isDescending, withId, withSqlQueryId, withSubQueryId

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.druid.query.Query

getMostSpecificId, optimizeForSegment, withDefaultSubQueryId, withLane, withPriority

Field Detail

CTX_KEY_OUTERMOST

public static final String CTX_KEY_OUTERMOST

This context flag corresponds to whether the query is running on the "outermost" process (i.e. the process the query is sent to).

See Also:

Constant Field Values

Constructor Detail

ScanQuery

public ScanQuery(DataSource dataSource,
                 QuerySegmentSpec querySegmentSpec,
                 VirtualColumns virtualColumns,
                 ScanQuery.ResultFormat resultFormat,
                 int batchSize,
                 long scanRowsOffset,
                 long scanRowsLimit,
                 ScanQuery.Order order,
                 DimFilter dimFilter,
                 List<String> columns,
                 Boolean legacy,
                 Map<String,Object> context)

Method Detail

getVirtualColumns

public VirtualColumns getVirtualColumns()

getResultFormat

public ScanQuery.ResultFormat getResultFormat()

getBatchSize

public int getBatchSize()

getScanRowsOffset

public long getScanRowsOffset()

Offset for this query; behaves like SQL "OFFSET". Zero means no offset. Negative values are invalid.

getScanRowsLimit

public long getScanRowsLimit()

Limit for this query; behaves like SQL "LIMIT". Will always be positive. Long.MAX_VALUE is used in situations where the user wants an effectively unlimited resultset.

isLimited

public boolean isLimited()

Returns whether this query is limited or not. Because Long.MAX_VALUE is used to signify unlimitedness, this is equivalent to getScanRowsLimit() != Long.Max_VALUE.

See Also:

getScanRowsLimit()

getOrder

public ScanQuery.Order getOrder()

getMaxRowsQueuedForOrdering

@Nullable
public Integer getMaxRowsQueuedForOrdering()

getMaxSegmentPartitionsOrderedInMemory

@Nullable
public Integer getMaxSegmentPartitionsOrderedInMemory()

hasFilters

public boolean hasFilters()

getFilter

public DimFilter getFilter()

getType

public String getType()

getColumns

public List<String> getColumns()

isLegacy

public Boolean isLegacy()

Compatibility mode with the legacy scan-query extension.

getResultOrdering

public com.google.common.collect.Ordering<ScanResultValue> getResultOrdering()

Description copied from class: BaseQuery

Default implementation of Query.getResultOrdering() that uses Ordering.natural(). If your query result type T is not Comparable, you must override this method.

Specified by:

getResultOrdering in interface Query<ScanResultValue>

Overrides:

getResultOrdering in class BaseQuery<ScanResultValue>

getRequiredColumns

@Nullable
public Set<String> getRequiredColumns()

Description copied from interface: Query

Returns the set of columns that this query will need to access out of its datasource. This method does not "look into" what the datasource itself is doing. For example, if a query is built on a QueryDataSource, this method will not return the columns used by that subquery. As another example, if a query is built on a JoinDataSource, this method will not return the columns from the underlying datasources that are used by the join condition, unless those columns are also used by this query in other ways. Returns null if the set of required columns cannot be known ahead of time.

withOffset

public ScanQuery withOffset(long newOffset)

withLimit

public ScanQuery withLimit(long newLimit)

withNonNullLegacy

public ScanQuery withNonNullLegacy(ScanQueryConfig scanQueryConfig)

withQuerySegmentSpec

public Query<ScanResultValue> withQuerySegmentSpec(QuerySegmentSpec querySegmentSpec)

Description copied from interface: Query

Returns a new query, identical to this one, but with a different associated QuerySegmentSpec. This often changes the behavior of Query.getRunner(QuerySegmentWalker), since most queries inherit that method from BaseQuery, which implements it by calling QuerySegmentSpec.lookup(org.apache.druid.query.Query<T>, org.apache.druid.query.QuerySegmentWalker).

withDataSource

public Query<ScanResultValue> withDataSource(DataSource dataSource)

withOverriddenContext

public Query<ScanResultValue> withOverriddenContext(Map<String,Object> contextOverrides)

equals

public boolean equals(Object o)

Overrides:

equals in class BaseQuery<ScanResultValue>

hashCode

public int hashCode()

Overrides:

hashCode in class BaseQuery<ScanResultValue>

toString

public String toString()

Overrides:

toString in class Object