de.lmu.ifi.dbs.elki.database

Interface Database

All Superinterfaces:

HierarchicalResult, Result

All Known Subinterfaces:

UpdatableDatabase

All Known Implementing Classes:

AbstractDatabase, HashmapDatabase, ProxyDatabase, StaticArrayDatabase

public interface Database
extends HierarchicalResult

Database specifies the requirements for any database implementation. Note that any implementing class is supposed to provide a constructor without parameters for dynamic instantiation.

Since:

0.1

Author:

Elke Achtert

Method Summary

Modifier and Type	Method and Description
void	accumulateDataStoreEvents() Collects all insertion, deletion and update events until flushDataStoreEvents() is called.
void	addDataStoreListener(DataStoreListener l) Adds a listener for the DataStoreEvent posted after the content of the database changes.
void	flushDataStoreEvents() Fires all collected insertion, deletion and update events as one DataStoreEvent, i.e. notifies all registered DataStoreListener how the content of the database has been changed since accumulateDataStoreEvents() has been called.
SingleObjectBundle	getBundle(DBIDRef id) Returns the DatabaseObject represented by the specified id.
<O> DistanceQuery<O>	getDistanceQuery(Relation<O> relation, DistanceFunction<? super O> distanceFunction, java.lang.Object... hints) Get the distance query for a particular distance function.
<O> KNNQuery<O>	getKNNQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a KNN query object for the given distance query.
<O> RangeQuery<O>	getRangeQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a range query object for the given distance query for radius-based neighbor search.
<O> Relation<O>	getRelation(TypeInformation restriction, java.lang.Object... hints) Get an object representation.
java.util.Collection<Relation<?>>	getRelations() Get all relations of a database.
<O> RKNNQuery<O>	getRKNNQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a rKNN query object for the given distance query.
<O> SimilarityQuery<O>	getSimilarityQuery(Relation<O> relation, SimilarityFunction<? super O> similarityFunction, java.lang.Object... hints) Get the similarity query for a particular similarity function.
<O> RangeQuery<O>	getSimilarityRangeQuery(SimilarityQuery<O> simQuery, java.lang.Object... hints) Get a range query object for the given distance query for radius-based neighbor search.
void	initialize() Initialize the database, for example by loading the input data.
void	removeDataStoreListener(DataStoreListener l) Removes a listener previously added with addDataStoreListener(DataStoreListener).

Methods inherited from interface de.lmu.ifi.dbs.elki.result.HierarchicalResult

getHierarchy, setHierarchy

Methods inherited from interface de.lmu.ifi.dbs.elki.result.Result

getLongName, getShortName

Method Detail

initialize

void initialize()

Initialize the database, for example by loading the input data. (Since this should NOT be done on construction time!)

getRelations

java.util.Collection<Relation<?>> getRelations()

Get all relations of a database.

Returns:

All relations in the database

getRelation

<O> Relation<O> getRelation(TypeInformation restriction,
                            java.lang.Object... hints)
                     throws NoSupportedDataTypeException

Get an object representation.

Type Parameters:

O - Object type

Parameters:

restriction - Type restriction

hints - Optimizer hints

Returns:

representation

Throws:

NoSupportedDataTypeException

getDistanceQuery

<O> DistanceQuery<O> getDistanceQuery(Relation<O> relation,
                                      DistanceFunction<? super O> distanceFunction,
                                      java.lang.Object... hints)

Get the distance query for a particular distance function.

Type Parameters:

O - Object type

Parameters:

relation - Relation used

distanceFunction - Distance function to use

hints - Optimizer hints

Returns:

Instance to query the database with this distance

getSimilarityQuery

<O> SimilarityQuery<O> getSimilarityQuery(Relation<O> relation,
                                          SimilarityFunction<? super O> similarityFunction,
                                          java.lang.Object... hints)

Get the similarity query for a particular similarity function.

Type Parameters:

O - Object type

Parameters:

relation - Relation used

similarityFunction - Similarity function to use

hints - Optimizer hints

Returns:

Instance to query the database with this similarity

getKNNQuery

<O> KNNQuery<O> getKNNQuery(DistanceQuery<O> distanceQuery,
                            java.lang.Object... hints)

Get a KNN query object for the given distance query. An index is used when possible, but it may fall back to a linear scan. Hints include:

• Integer: maximum value for k needed
• DatabaseQuery.HINT_BULK bulk query needed

Type Parameters:

O - Object type

Parameters:

distanceQuery - Distance query

hints - Optimizer hints

Returns:

KNN Query object

getRangeQuery

<O> RangeQuery<O> getRangeQuery(DistanceQuery<O> distanceQuery,
                                java.lang.Object... hints)

Get a range query object for the given distance query for radius-based neighbor search. (Range queries in ELKI refers to radius-based ranges, not rectangular query windows.) An index is used when possible, but it may fall back to a linear scan. Hints include:

• Double: Maximum query range that will be used.
• DatabaseQuery.HINT_BULK bulk query needed

Type Parameters:

O - Object type

Parameters:

distanceQuery - Distance query

hints - Optimizer hints

Returns:

KNN Query object

getSimilarityRangeQuery

<O> RangeQuery<O> getSimilarityRangeQuery(SimilarityQuery<O> simQuery,
                                          java.lang.Object... hints)

Get a range query object for the given distance query for radius-based neighbor search. (Range queries in ELKI refers to radius-based ranges, not rectangular query windows.) An index is used when possible, but it may fall back to a linear scan. Hints include:

• Double: Minimum query similarity that will be used.
• DatabaseQuery.HINT_BULK bulk query needed

Type Parameters:

O - Object type

Parameters:

simQuery - Similarity query

hints - Optimizer hints

Returns:

KNN Query object

getRKNNQuery

<O> RKNNQuery<O> getRKNNQuery(DistanceQuery<O> distanceQuery,
                              java.lang.Object... hints)

Get a rKNN query object for the given distance query. An index is used when possible, but it may fall back to a linear scan. Hints include:

• Integer: maximum value for k needed
• DatabaseQuery.HINT_BULK bulk query needed

Type Parameters:

O - Object type

Parameters:

distanceQuery - Distance query

hints - Optimizer hints

Returns:

KNN Query object

getBundle

SingleObjectBundle getBundle(DBIDRef id)

Returns the DatabaseObject represented by the specified id.

Parameters:

id - the id of the Object to be obtained from the Database

Returns:

Bundle containing the objects' data

addDataStoreListener

void addDataStoreListener(DataStoreListener l)

Adds a listener for the DataStoreEvent posted after the content of the database changes.

Parameters:

l - the listener to add

See Also:

removeDataStoreListener(DataStoreListener), DataStoreListener, DataStoreEvent

removeDataStoreListener

void removeDataStoreListener(DataStoreListener l)

Removes a listener previously added with addDataStoreListener(DataStoreListener).

Parameters:

l - the listener to remove

See Also:

addDataStoreListener(DataStoreListener), DataStoreListener, DataStoreEvent

accumulateDataStoreEvents

void accumulateDataStoreEvents()

Collects all insertion, deletion and update events until flushDataStoreEvents() is called.

See Also:

DataStoreEvent

flushDataStoreEvents

void flushDataStoreEvents()

Fires all collected insertion, deletion and update events as one DataStoreEvent, i.e. notifies all registered DataStoreListener how the content of the database has been changed since accumulateDataStoreEvents() has been called.

See Also:

DataStoreListener, DataStoreEvent