org.apache.druid.segment.column

Class RowSignature.Builder

java.lang.Object

org.apache.druid.segment.column.RowSignature.Builder

Enclosing class:

RowSignature

public static class RowSignature.Builder
extends Object

Method Summary

Modifier and Type	Method and Description
RowSignature.Builder	add(String columnName, ColumnType columnType) Add a column to this signature.
RowSignature.Builder	addAggregators(List<AggregatorFactory> aggregators, RowSignature.Finalization finalization) Adds aggregations to a signature.
RowSignature.Builder	addAll(RowSignature other)
RowSignature.Builder	addDimensions(List<DimensionSpec> dimensions)
RowSignature.Builder	addPostAggregators(List<PostAggregator> postAggregators) Adds post-aggregators to a signature.
RowSignature.Builder	addTimeColumn()
RowSignature	build()

Methods inherited from class java.lang.Object

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

Method Detail

add

public RowSignature.Builder add(String columnName,
                                @Nullable
                                ColumnType columnType)

Add a column to this signature.

Parameters:

columnName - name, must be nonnull

columnType - type, may be null if unknown

addAll

public RowSignature.Builder addAll(RowSignature other)

addTimeColumn

public RowSignature.Builder addTimeColumn()

addDimensions

public RowSignature.Builder addDimensions(List<DimensionSpec> dimensions)

addAggregators

public RowSignature.Builder addAggregators(List<AggregatorFactory> aggregators,
                                           RowSignature.Finalization finalization)

Adds aggregations to a signature. RowSignature.Finalization.YES will add finalized types and RowSignature.Finalization.NO will add intermediate types. RowSignature.Finalization.UNKNOWN will add the intermediate / finalized type when they are the same. Otherwise, it will add a null type.

Parameters:

aggregators - list of aggregation functions

finalization - whether the aggregator results will be finalized

addPostAggregators

public RowSignature.Builder addPostAggregators(List<PostAggregator> postAggregators)

Adds post-aggregators to a signature. Note: to ensure types are computed properly, post-aggregators must be added *after* any columns that they depend on, and they must be added in the order that the query engine will compute them. This method assumes that post-aggregators are computed in order, and that they can refer to earlier post-aggregators but not to later ones.

build

public RowSignature build()