org.apache.drill.metastore.metadata

Class NonInterestingColumnsMetadata

java.lang.Object

org.apache.drill.metastore.metadata.NonInterestingColumnsMetadata

All Implemented Interfaces:

Metadata

public class NonInterestingColumnsMetadata
extends Object
implements Metadata

Represents a metadata for the non-interesting columns. Since the refresh command doesn't store the non-interesting columns stats in the cache file, there is a need to mark column statistics of non-interesting as unknown to differentiate the non-interesting columns from non-existent columns. Since the sole purpose of this class is to store column statistics for non-interesting columns, some methods like getSchema, get, getColumn are not applicable to NonInterestingColumnsMetadata.

Constructor Summary

Constructors

Constructor and Description
NonInterestingColumnsMetadata(Map<SchemaPath,ColumnStatistics<?>> columnsStatistics)

Method Summary

Modifier and Type	Method and Description
boolean	containsExactStatistics(StatisticsKind<?> statisticsKind) Checks whether specified statistics kind is set in this non-column statistics and it corresponds to the exact statistics value.
ColumnMetadata	getColumn(SchemaPath name) Returns metadata description for the specified column
Map<SchemaPath,ColumnStatistics<?>>	getColumnsStatistics() Returns statistics stored in current metadata represented as Map of column SchemaPaths and corresponding ColumnStatistics.
ColumnStatistics<?>	getColumnStatistics(SchemaPath columnName) Returns statistics for specified column stored in current metadata.
MetadataInfo	getMetadataInfo()
TupleMetadata	getSchema() Returns schema stored in current metadata represented as TupleMetadata.
<V> V	getStatistic(StatisticsKind<V> statisticsKind) Returns value of non-column statistics which corresponds to specified StatisticsKind.
<V> V	getStatisticsForColumn(SchemaPath columnName, StatisticsKind<V> statisticsKind) Returns value of column statistics which corresponds to specified StatisticsKind for column with specified columnName.
TableInfo	getTableInfo()
TableMetadataUnit	toMetadataUnit() Converts Metadata implementation into TableMetadataUnit instance which will be used to write data into Drill Metastore Tables.

Methods inherited from class java.lang.Object

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

Constructor Detail

NonInterestingColumnsMetadata

public NonInterestingColumnsMetadata(Map<SchemaPath,ColumnStatistics<?>> columnsStatistics)

Method Detail

getColumnsStatistics

public Map<SchemaPath,ColumnStatistics<?>> getColumnsStatistics()

Description copied from interface: Metadata

Returns statistics stored in current metadata represented as Map of column SchemaPaths and corresponding ColumnStatistics.

Specified by:

getColumnsStatistics in interface Metadata

Returns:

statistics stored in current metadata

getColumnStatistics

public ColumnStatistics<?> getColumnStatistics(SchemaPath columnName)

Description copied from interface: Metadata

Returns statistics for specified column stored in current metadata.

Specified by:

getColumnStatistics in interface Metadata

Parameters:

columnName - column whose statistics should be returned

Returns:

statistics for specified column

getSchema

public TupleMetadata getSchema()

Description copied from interface: Metadata

Returns schema stored in current metadata represented as TupleMetadata.

Specified by:

getSchema in interface Metadata

Returns:

schema stored in current metadata

getStatistic

public <V> V getStatistic(StatisticsKind<V> statisticsKind)

Description copied from interface: Metadata

Returns value of non-column statistics which corresponds to specified StatisticsKind.

Specified by:

getStatistic in interface Metadata

Parameters:

statisticsKind - statistics kind whose value should be returned

Returns:

value of non-column statistics

containsExactStatistics

public boolean containsExactStatistics(StatisticsKind<?> statisticsKind)

Description copied from interface: Metadata

Checks whether specified statistics kind is set in this non-column statistics and it corresponds to the exact statistics value.

Specified by:

containsExactStatistics in interface Metadata

Parameters:

statisticsKind - statistics kind to check

Returns:

true if value which corresponds to the specified statistics kind is exact

getStatisticsForColumn

public <V> V getStatisticsForColumn(SchemaPath columnName,
                                    StatisticsKind<V> statisticsKind)

Description copied from interface: Metadata

Returns value of column statistics which corresponds to specified StatisticsKind for column with specified columnName.

Specified by:

getStatisticsForColumn in interface Metadata

Parameters:

columnName - name of the column

statisticsKind - statistics kind whose value should be returned

Returns:

value of column statistics

getColumn

public ColumnMetadata getColumn(SchemaPath name)

Description copied from interface: Metadata

Returns metadata description for the specified column

Specified by:

getColumn in interface Metadata

Parameters:

name - column name, whose metadata type info should be returned

Returns:

ColumnMetadata schema description of the column

getTableInfo

public TableInfo getTableInfo()

Specified by:

getTableInfo in interface Metadata

getMetadataInfo

public MetadataInfo getMetadataInfo()

Specified by:

getMetadataInfo in interface Metadata

toMetadataUnit

public TableMetadataUnit toMetadataUnit()

Description copied from interface: Metadata

Converts Metadata implementation into TableMetadataUnit instance which will be used to write data into Drill Metastore Tables.

Specified by:

toMetadataUnit in interface Metadata

Returns:

metadata unit instance