io.druid.segment.filter

Class Filters

java.lang.Object

io.druid.segment.filter.Filters

public class Filters
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static List<ValueType>	FILTERABLE_TYPES

Constructor Summary

Constructors

Constructor and Description
Filters()

Method Summary

Modifier and Type	Method and Description
static ImmutableBitmap	allFalse(BitmapIndexSelector selector)
static ImmutableBitmap	allTrue(BitmapIndexSelector selector)
static Filter	convertToCNF(Filter current)
static Filter	convertToCNFFromQueryContext(Query query, Filter filter)
static double	estimateSelectivity(BitmapIndex bitmapIndex, it.unimi.dsi.fastutil.ints.IntList bitmaps, long totalNumRows) Return an estimated selectivity for bitmaps for the dimension values given by dimValueIndexes.
static double	estimateSelectivity(Iterator<ImmutableBitmap> bitmaps, long totalNumRows) Return an estimated selectivity for bitmaps given by an iterator.
static double	estimateSelectivity(String dimension, BitmapIndexSelector indexSelector, com.google.common.base.Predicate<String> predicate) Return an estimated selectivity for bitmaps of all values matching the given predicate.
static ValueMatcher	getLongPredicateMatcher(LongColumnSelector longSelector, DruidLongPredicate predicate)
static ValueMatcher	getLongValueMatcher(LongColumnSelector longSelector, String value)
static ValueMatcher	makeValueMatcher(ColumnSelectorFactory columnSelectorFactory, String columnName, DruidPredicateFactory predicateFactory) Create a ValueMatcher that applies a predicate to row values.
static ValueMatcher	makeValueMatcher(ColumnSelectorFactory columnSelectorFactory, String columnName, String value) Create a ValueMatcher that compares row values to the provided string.
static ImmutableBitmap	matchPredicate(String dimension, BitmapIndexSelector selector, com.google.common.base.Predicate<String> predicate) Return the union of bitmaps for all values matching a particular predicate.
static Iterable<ImmutableBitmap>	matchPredicateNoUnion(String dimension, BitmapIndexSelector selector, com.google.common.base.Predicate<String> predicate) Return an iterable of bitmaps for all values matching a particular predicate.
static Filter	toFilter(DimFilter dimFilter) Convert a DimFilter to a Filter.
static List<Filter>	toFilters(List<DimFilter> dimFilters) Convert a list of DimFilters to a list of Filters.

Methods inherited from class java.lang.Object

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

Field Detail

FILTERABLE_TYPES

public static final List<ValueType> FILTERABLE_TYPES

Constructor Detail

Filters

public Filters()

Method Detail

toFilters

public static List<Filter> toFilters(List<DimFilter> dimFilters)

Convert a list of DimFilters to a list of Filters.

Parameters:

dimFilters - list of DimFilters, should all be non-null

Returns:

list of Filters

toFilter

public static Filter toFilter(DimFilter dimFilter)

Convert a DimFilter to a Filter.

Parameters:

dimFilter - dimFilter

Returns:

converted filter, or null if input was null

makeValueMatcher

public static ValueMatcher makeValueMatcher(ColumnSelectorFactory columnSelectorFactory,
                                            String columnName,
                                            String value)

Create a ValueMatcher that compares row values to the provided string.

An implementation of this method should be able to handle dimensions of various types.

Parameters:

columnSelectorFactory - Selector for columns.

columnName - The column to filter.

value - The value to match against, represented as a String.

Returns:

An object that matches row values on the provided value.

makeValueMatcher

public static ValueMatcher makeValueMatcher(ColumnSelectorFactory columnSelectorFactory,
                                            String columnName,
                                            DruidPredicateFactory predicateFactory)

Create a ValueMatcher that applies a predicate to row values.

The caller provides a predicate factory that can create a predicate for each value type supported by Druid. See DruidPredicateFactory for more information.

When creating the ValueMatcher, the ValueMatcherFactory implementation should decide what type of predicate to create from the predicate factory based on the ValueType of the specified dimension.

Parameters:

columnSelectorFactory - Selector for columns.

columnName - The column to filter.

predicateFactory - Predicate factory

Returns:

An object that applies a predicate to row values

allFalse

public static ImmutableBitmap allFalse(BitmapIndexSelector selector)

allTrue

public static ImmutableBitmap allTrue(BitmapIndexSelector selector)

matchPredicate

public static ImmutableBitmap matchPredicate(String dimension,
                                             BitmapIndexSelector selector,
                                             com.google.common.base.Predicate<String> predicate)

Return the union of bitmaps for all values matching a particular predicate.

Parameters:

dimension - dimension to look at

selector - bitmap selector

predicate - predicate to use

Returns:

bitmap of matching rows

See Also:

estimateSelectivity(String, BitmapIndexSelector, Predicate)

matchPredicateNoUnion

public static Iterable<ImmutableBitmap> matchPredicateNoUnion(String dimension,
                                                              BitmapIndexSelector selector,
                                                              com.google.common.base.Predicate<String> predicate)

Return an iterable of bitmaps for all values matching a particular predicate. Unioning these bitmaps yields the same result that matchPredicate(String, BitmapIndexSelector, Predicate) would have returned.

Parameters:

dimension - dimension to look at

selector - bitmap selector

predicate - predicate to use

Returns:

iterable of bitmaps of matching rows

estimateSelectivity

public static double estimateSelectivity(String dimension,
                                         BitmapIndexSelector indexSelector,
                                         com.google.common.base.Predicate<String> predicate)

Return an estimated selectivity for bitmaps of all values matching the given predicate.

Parameters:

dimension - dimension to look at

indexSelector - bitmap selector

predicate - predicate to use

Returns:

estimated selectivity

See Also:

matchPredicate(String, BitmapIndexSelector, Predicate)

estimateSelectivity

public static double estimateSelectivity(BitmapIndex bitmapIndex,
                                         it.unimi.dsi.fastutil.ints.IntList bitmaps,
                                         long totalNumRows)

Return an estimated selectivity for bitmaps for the dimension values given by dimValueIndexes.

Parameters:

bitmapIndex - bitmap index

bitmaps - bitmaps to extract, by index

totalNumRows - number of rows in the column associated with this bitmap index

Returns:

estimated selectivity

estimateSelectivity

public static double estimateSelectivity(Iterator<ImmutableBitmap> bitmaps,
                                         long totalNumRows)

Return an estimated selectivity for bitmaps given by an iterator.

Parameters:

bitmaps - iterator of bitmaps

totalNumRows - number of rows in the column associated with this bitmap index

Returns:

estimated selectivity

getLongValueMatcher

public static ValueMatcher getLongValueMatcher(LongColumnSelector longSelector,
                                               String value)

getLongPredicateMatcher

public static ValueMatcher getLongPredicateMatcher(LongColumnSelector longSelector,
                                                   DruidLongPredicate predicate)

convertToCNFFromQueryContext

public static Filter convertToCNFFromQueryContext(Query query,
                                                  Filter filter)

convertToCNF

public static Filter convertToCNF(Filter current)