Package org.apache.druid.query.groupby.epinephelinae

Class RowBasedGrouperHelper

java.lang.Object

org.apache.druid.query.groupby.epinephelinae.RowBasedGrouperHelper

public class RowBasedGrouperHelper
extends Object

This class contains shared code between GroupByMergingQueryRunner and GroupByRowProcessor.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	RowBasedGrouperHelper.RowBasedKey

Method Summary

Modifier and Type	Method	Description
static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>>	createGrouperAccumulatorPair(GroupByQuery query, GroupByQuery subquery, GroupByQueryConfig config, DruidProcessingConfig processingConfig, com.google.common.base.Supplier<ByteBuffer> bufferSupplier, ReferenceCountingResourceHolder<ByteBuffer> combineBufferHolder, int concurrencyHint, LimitedTemporaryStorage temporaryStorage, com.fasterxml.jackson.databind.ObjectMapper spillMapper, com.google.common.util.concurrent.ListeningExecutorService grouperSorter, int priority, boolean hasQueryTimeout, long queryTimeoutAt, int mergeBufferSize, GroupByStatsProvider.PerQueryStats perQueryStats)	Create a Grouper that groups according to the dimensions and aggregators in "query", along with an Accumulator that accepts ResultRows and forwards them to the grouper.
static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>>	createGrouperAccumulatorPair(GroupByQuery query, GroupByQuery subquery, GroupByQueryConfig config, DruidProcessingConfig processingConfig, com.google.common.base.Supplier<ByteBuffer> bufferSupplier, LimitedTemporaryStorage temporaryStorage, com.fasterxml.jackson.databind.ObjectMapper spillMapper, int mergeBufferSize, GroupByStatsProvider.PerQueryStats perQueryStats)	Create a single-threaded grouper and accumulator.
static ColumnSelectorFactory	createResultRowBasedColumnSelectorFactory(GroupByQuery query, com.google.common.base.Supplier<ResultRow> supplier, RowSignature.Finalization finalization)	Creates a ColumnSelectorFactory that can read rows which originate as results of the provided "query".
static CloseableGrouperIterator<RowBasedGrouperHelper.RowBasedKey,ResultRow>	makeGrouperIterator(Grouper<RowBasedGrouperHelper.RowBasedKey> grouper, GroupByQuery query, Closeable closeable)
static CloseableGrouperIterator<RowBasedGrouperHelper.RowBasedKey,ResultRow>	makeGrouperIterator(Grouper<RowBasedGrouperHelper.RowBasedKey> grouper, GroupByQuery query, List<DimensionSpec> dimsToInclude, Closeable closeable)

Methods inherited from class java.lang.Object

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

Method Details

createGrouperAccumulatorPair

public static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>> createGrouperAccumulatorPair(GroupByQuery query,
 @Nullable
 GroupByQuery subquery,
 GroupByQueryConfig config,
 DruidProcessingConfig processingConfig,
 com.google.common.base.Supplier<ByteBuffer> bufferSupplier,
 LimitedTemporaryStorage temporaryStorage,
 com.fasterxml.jackson.databind.ObjectMapper spillMapper,
 int mergeBufferSize,
 GroupByStatsProvider.PerQueryStats perQueryStats)

Create a single-threaded grouper and accumulator.

createGrouperAccumulatorPair

public static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>> createGrouperAccumulatorPair(GroupByQuery query,
 @Nullable
 GroupByQuery subquery,
 GroupByQueryConfig config,
 DruidProcessingConfig processingConfig,
 com.google.common.base.Supplier<ByteBuffer> bufferSupplier,
 @Nullable
 ReferenceCountingResourceHolder<ByteBuffer> combineBufferHolder,
 int concurrencyHint,
 LimitedTemporaryStorage temporaryStorage,
 com.fasterxml.jackson.databind.ObjectMapper spillMapper,
 @Nullable
 com.google.common.util.concurrent.ListeningExecutorService grouperSorter,
 int priority,
 boolean hasQueryTimeout,
 long queryTimeoutAt,
 int mergeBufferSize,
 GroupByStatsProvider.PerQueryStats perQueryStats)

Create a Grouper that groups according to the dimensions and aggregators in "query", along with an Accumulator that accepts ResultRows and forwards them to the grouper.

The pair will operate in one of two modes:

1) Combining mode (used if "subquery" is null). In this mode, filters from the "query" are ignored, and its aggregators are converted into combining form. The input ResultRows are assumed to be partially-grouped results originating from the provided "query".

2) Subquery mode (used if "subquery" is nonnull). In this mode, filters from the "query" (both intervals and dim filters) are respected, and its aggregators are used in standard (not combining) form. The input ResultRows are assumed to be results originating from the provided "subquery".

Parameters:

query - query that we are grouping for

subquery - optional subquery that we are receiving results from (see combining vs. subquery mode above)

config - groupBy query config

processingConfig - processing config

bufferSupplier - supplier of merge buffers

combineBufferHolder - holder of combine buffers. Unused if concurrencyHint = -1, and may be null in that case

concurrencyHint - -1 for single-threaded Grouper, >=1 for concurrent Grouper

temporaryStorage - temporary storage used for spilling from the Grouper

spillMapper - object mapper used for spilling from the Grouper

grouperSorter - executor service used for parallel combining. Unused if concurrencyHint = -1, and may be null in that case

priority - query priority

hasQueryTimeout - whether or not this query has a timeout

queryTimeoutAt - when this query times out, in milliseconds since the epoch

mergeBufferSize - size of the merge buffers from "bufferSupplier"

createResultRowBasedColumnSelectorFactory

public static ColumnSelectorFactory createResultRowBasedColumnSelectorFactory(GroupByQuery query,
 com.google.common.base.Supplier<ResultRow> supplier,
 RowSignature.Finalization finalization)

Creates a ColumnSelectorFactory that can read rows which originate as results of the provided "query".

Parameters:

query - a groupBy query

supplier - supplier of result rows from the query

finalization - whether the column capabilities reported by this factory should reflect finalized types

makeGrouperIterator

public static CloseableGrouperIterator<RowBasedGrouperHelper.RowBasedKey,ResultRow> makeGrouperIterator(Grouper<RowBasedGrouperHelper.RowBasedKey> grouper,
 GroupByQuery query,
 Closeable closeable)

makeGrouperIterator

public static CloseableGrouperIterator<RowBasedGrouperHelper.RowBasedKey,ResultRow> makeGrouperIterator(Grouper<RowBasedGrouperHelper.RowBasedKey> grouper,
 GroupByQuery query,
 @Nullable
 List<DimensionSpec> dimsToInclude,
 Closeable closeable)