Package org.apache.druid.segment.metadata

Class CoordinatorSegmentMetadataCache

java.lang.Object

org.apache.druid.segment.metadata.AbstractSegmentMetadataCache<DataSourceInformation>

org.apache.druid.segment.metadata.CoordinatorSegmentMetadataCache

public class CoordinatorSegmentMetadataCache
extends AbstractSegmentMetadataCache<DataSourceInformation>

Coordinator-side cache of segment metadata that combines segments to build datasources. The cache provides metadata about a datasource, see DataSourceInformation.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.druid.segment.metadata.AbstractSegmentMetadataCache

AbstractSegmentMetadataCache.ColumnTypeMergePolicy, AbstractSegmentMetadataCache.FirstTypeMergePolicy, AbstractSegmentMetadataCache.LeastRestrictiveTypeMergePolicy

Field Summary

Fields inherited from class org.apache.druid.segment.metadata.AbstractSegmentMetadataCache

callbackExec, dataSourcesNeedingRebuild, emitter, isServerViewInitialized, lock, mutableSegments, ROW_SIGNATURE_INTERNER, SEGMENT_ORDER, segmentMetadataInfo, segmentsNeedingRefresh, tables

Constructor Summary

Constructors

Constructor	Description
CoordinatorSegmentMetadataCache(QueryLifecycleFactory queryLifecycleFactory, CoordinatorServerView serverView, SegmentMetadataCacheConfig config, Escalator escalator, InternalQueryConfig internalQueryConfig, org.apache.druid.java.util.emitter.service.ServiceEmitter emitter, CentralizedDatasourceSchemaConfig centralizedDatasourceSchemaConfig)

Method Summary

Modifier and Type	Method	Description
void	refresh(Set<org.apache.druid.timeline.SegmentId> segmentsToRefresh, Set<String> dataSourcesToRebuild)	Executes SegmentMetadataQuery to fetch schema information for each segment in the refresh list.

Methods inherited from class org.apache.druid.segment.metadata.AbstractSegmentMetadataCache

addSegment, awaitInitialization, buildDataSourceRowSignature, doInLock, getAvailableSegmentMetadata, getDatasource, getDataSourceInformationMap, getDatasourceNames, getDataSourcesNeedingRebuild, getMutableSegments, getSegmentMetadataSnapshot, getSegmentsNeedingRefresh, getTotalSegments, markDataSourceAsNeedRebuild, refreshSegments, removeSegment, removeServerSegment, runSegmentMetadataQuery, setAvailableSegmentMetadata, start, stop

Methods inherited from class java.lang.Object

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

Constructor Detail

CoordinatorSegmentMetadataCache

@Inject
public CoordinatorSegmentMetadataCache(QueryLifecycleFactory queryLifecycleFactory,
                                       CoordinatorServerView serverView,
                                       SegmentMetadataCacheConfig config,
                                       Escalator escalator,
                                       InternalQueryConfig internalQueryConfig,
                                       org.apache.druid.java.util.emitter.service.ServiceEmitter emitter,
                                       CentralizedDatasourceSchemaConfig centralizedDatasourceSchemaConfig)

Method Detail

refresh

public void refresh(Set<org.apache.druid.timeline.SegmentId> segmentsToRefresh,
                    Set<String> dataSourcesToRebuild)
             throws IOException

Executes SegmentMetadataQuery to fetch schema information for each segment in the refresh list. The schema information for individual segments is combined to construct a table schema, which is then cached.

Specified by:

refresh in class AbstractSegmentMetadataCache<DataSourceInformation>

Parameters:

segmentsToRefresh - segments for which the schema might have changed

dataSourcesToRebuild - datasources for which the schema might have changed

Throws:

IOException - when querying segment from data nodes and tasks