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 GroupByMergingQueryRunnerV2 and GroupByRowProcessor.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RowBasedGrouperHelper.RowBasedKey

Method Summary

Modifier and Type	Method and Description
static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>>	createGrouperAccumulatorPair(GroupByQuery query, GroupByQuery subquery, GroupByQueryConfig config, com.google.common.base.Supplier<ByteBuffer> bufferSupplier, LimitedTemporaryStorage temporaryStorage, com.fasterxml.jackson.databind.ObjectMapper spillMapper, int mergeBufferSize) Create a single-threaded grouper and accumulator.
static Pair<Grouper<RowBasedGrouperHelper.RowBasedKey>,Accumulator<AggregateResult,ResultRow>>	createGrouperAccumulatorPair(GroupByQuery query, GroupByQuery subquery, GroupByQueryConfig config, 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) 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 ColumnSelectorFactory	createResultRowBasedColumnSelectorFactory(GroupByQuery query, com.google.common.base.Supplier<ResultRow> supplier) 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<String> dimsToInclude, Closeable closeable)

Methods inherited from class java.lang.Object

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

Method Detail

createGrouperAccumulatorPair

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

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,
                                                                                                                                   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)

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

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)

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

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<String> dimsToInclude,
                                                                                                        Closeable closeable)