org.apache.druid.query.filter

Interface BooleanFilter

All Superinterfaces:

Filter

All Known Implementing Classes:

AndFilter, OrFilter

public interface BooleanFilter
extends Filter

Field Summary

Fields

Modifier and Type	Field and Description
static ValueMatcher[]	EMPTY_VALUE_MATCHER_ARRAY

Method Summary

Modifier and Type	Method and Description
Set<Filter>	getFilters()
default Set<String>	getRequiredColumns() Set of columns used by a filter.
ValueMatcher	makeMatcher(BitmapIndexSelector selector, ColumnSelectorFactory columnSelectorFactory, RowOffsetMatcherFactory rowOffsetMatcherFactory) Get a ValueMatcher that applies this filter to row values.
default boolean	shouldUseBitmapIndex(BitmapIndexSelector selector) Determine if a filter *should* use a bitmap index based on information collected from the supplied BitmapIndexSelector.
default boolean	supportsBitmapIndex(BitmapIndexSelector selector) Indicates whether this filter can return a bitmap index for filtering, based on the information provided by the input BitmapIndexSelector.
default boolean	supportsSelectivityEstimation(ColumnSelector columnSelector, BitmapIndexSelector indexSelector) Indicates whether this filter supports selectivity estimation.

Methods inherited from interface org.apache.druid.query.filter.Filter

canVectorizeMatcher, estimateSelectivity, getBitmapIndex, getBitmapResult, makeMatcher, makeVectorMatcher, rewriteRequiredColumns, supportsRequiredColumnRewrite

Field Detail

EMPTY_VALUE_MATCHER_ARRAY

static final ValueMatcher[] EMPTY_VALUE_MATCHER_ARRAY

Method Detail

getFilters

Set<Filter> getFilters()

makeMatcher

ValueMatcher makeMatcher(BitmapIndexSelector selector,
                         ColumnSelectorFactory columnSelectorFactory,
                         RowOffsetMatcherFactory rowOffsetMatcherFactory)

Get a ValueMatcher that applies this filter to row values. Unlike makeMatcher(ValueMatcherFactory), this method allows the Filter to utilize bitmap indexes. An implementation should either: - return a ValueMatcher that checks row values, using the provided ValueMatcherFactory - or, if possible, get a bitmap index for this filter using the BitmapIndexSelector, and return a ValueMatcher that checks the current row offset, created using the bitmap index.

Parameters:

selector - Object used to retrieve bitmap indexes

columnSelectorFactory - Object used to select columns for making ValueMatchers

rowOffsetMatcherFactory - Object used to create RowOffsetMatchers

Returns:

ValueMatcher that applies this filter

getRequiredColumns

default Set<String> getRequiredColumns()

Description copied from interface: Filter

Set of columns used by a filter. If Filter.supportsBitmapIndex(org.apache.druid.query.filter.BitmapIndexSelector) returns true, all columns returned by this method can be expected to have a bitmap index retrievable via BitmapIndexSelector.getBitmapIndex(String)

Specified by:

getRequiredColumns in interface Filter

supportsBitmapIndex

default boolean supportsBitmapIndex(BitmapIndexSelector selector)

Description copied from interface: Filter

Indicates whether this filter can return a bitmap index for filtering, based on the information provided by the input BitmapIndexSelector. Returning a value of true here guarantees that Filter.getBitmapIndex(BitmapIndexSelector) will return a non-null BitmapIndexSelector, and also that all columns specified in Filter.getRequiredColumns() have a bitmap index retrievable via BitmapIndexSelector.getBitmapIndex(String).

Specified by:

supportsBitmapIndex in interface Filter

Parameters:

selector - Object used to retrieve bitmap indexes

Returns:

true if this Filter can provide a bitmap index using the selector, false otherwise.

shouldUseBitmapIndex

default boolean shouldUseBitmapIndex(BitmapIndexSelector selector)

Description copied from interface: Filter

Determine if a filter *should* use a bitmap index based on information collected from the supplied BitmapIndexSelector. This method differs from Filter.supportsBitmapIndex(BitmapIndexSelector) in that the former only indicates if a bitmap index is available and Filter.getBitmapIndex(BitmapIndexSelector) may be used. If shouldUseFilter(selector) returns true, Filter.supportsBitmapIndex(org.apache.druid.query.filter.BitmapIndexSelector) must also return true when called with the same selector object. Returning a value of true here guarantees that Filter.getBitmapIndex(BitmapIndexSelector) will return a non-null BitmapIndexSelector, and also that all columns specified in Filter.getRequiredColumns() have a bitmap index retrievable via BitmapIndexSelector.getBitmapIndex(String). Implementations of this methods typically consider a FilterTuning to make decisions about when to use an available index. A "standard" implementation of this is available to all Filter implementations in Filters.shouldUseBitmapIndex(Filter, BitmapIndexSelector, FilterTuning).

Specified by:

shouldUseBitmapIndex in interface Filter

Parameters:

selector - Object used to retrieve bitmap indexes and provide information about the column

Returns:

true if this Filter should provide a bitmap index using the selector, false otherwise.

supportsSelectivityEstimation

default boolean supportsSelectivityEstimation(ColumnSelector columnSelector,
                                              BitmapIndexSelector indexSelector)

Description copied from interface: Filter

Indicates whether this filter supports selectivity estimation. A filter supports selectivity estimation if it supports bitmap index and the dimension which the filter evaluates does not have multi values.

Specified by:

supportsSelectivityEstimation in interface Filter

Parameters:

columnSelector - Object to check the dimension has multi values.

indexSelector - Object used to retrieve bitmap indexes

Returns:

true if this Filter supports selectivity estimation, false otherwise.