org.apache.druid.query.groupby.orderby

Interface LimitSpec

All Superinterfaces:

Cacheable

All Known Implementing Classes:

DefaultLimitSpec, NoopLimitSpec

public interface LimitSpec
extends Cacheable

Method Summary

Modifier and Type	Method and Description
com.google.common.base.Function<Sequence<ResultRow>,Sequence<ResultRow>>	build(GroupByQuery query) Returns a function that applies a limit to an input sequence that is assumed to be sorted on dimensions.
LimitSpec	filterColumns(Set<String> names) Discard sorting columns not contained in given set.
LimitSpec	merge(LimitSpec other)
static LimitSpec	nullToNoopLimitSpec(LimitSpec limitSpec)

Methods inherited from interface org.apache.druid.java.util.common.Cacheable

getCacheKey

Method Detail

nullToNoopLimitSpec

static LimitSpec nullToNoopLimitSpec(@Nullable
                                     LimitSpec limitSpec)

build

com.google.common.base.Function<Sequence<ResultRow>,Sequence<ResultRow>> build(GroupByQuery query)

Returns a function that applies a limit to an input sequence that is assumed to be sorted on dimensions.

Parameters:

query - the query that this limit spec belongs to

Returns:

limit function

merge

LimitSpec merge(LimitSpec other)

filterColumns

LimitSpec filterColumns(Set<String> names)

Discard sorting columns not contained in given set. This is used when generating new queries, e.g. to process subtotal spec in GroupBy query.

Parameters:

names - columns names to keep

Returns:

new LimitSpec that works with fitlered set of columns