YapDatabaseRTreeIndex

@interface YapDatabaseRTreeIndex : YapDatabaseExtension

Welcome to YapDatabase! https://github.com/yapstudios/YapDatabase

The project wiki has a wealth of documentation if you have any questions. https://github.com/yapstudios/YapDatabase/wiki

YapDatabaseRTreeIndex is an extension which allows you to add an additional geometrical index for fast searching.

That is, it allows you to create an index within sqlite for geometrical properties of your objects. You can then issue queries to find or enumerate objects. Examples:

enumerate all people in a bounding-box
enumerate all regions overlapping a bounding-box

Note:

The sqlite3 r-tree documentation https://www.sqlite.org/rtree.html states that

By default, coordinates are stored in an RTree using 32-bit floating point values. When a coordinate cannot be exactly represented by a 32-bit floating point number, the lower-bound coordinates are rounded down and the upper-bound coordinates are rounded up. Thus, bounding boxes might be slightly larger than specified, but will never be any smaller. This is exactly what is desired for doing the more common overlapping queries where the application wants to find every entry in the RTree that overlaps a query bounding box. Rounding the entry bounding boxes outward might cause a few extra entries to appears in an overlapping query if the edge of the entry bounding box corresponds to an edge of the query bounding box. But the overlapping query will never miss a valid table entry.

so coordinates in the r-tree might differ slightly from the ones you are giving the app, in particular if you are using Double values.

For more information, see the wiki article about rtree indexes: https://github.com/yapstudios/YapDatabase/wiki/RTree-Indexes


                    
                    
                    -initWithSetup:handler:

Creates a new rtree index extension. After creation, you’ll need to register the extension with the database system.

See

YapDatabaseRTreeIndexSetup

See

YapDatabaseRTreeIndexHandler

See

YapDatabase registerExtension:withName:

Declaration

Objective-C

- (id)initWithSetup:(YapDatabaseRTreeIndexSetup *)setup
            handler:(YapDatabaseRTreeIndexHandler *)handler;

Swift

init!(setup: YapDatabaseRTreeIndexSetup!, handler: YapDatabaseRTreeIndexHandler!)

Parameters

`setup`	A YapDatabaseRTreeIndexSetup instance allows you to specify the column names. The column names can be whatever you want, with a few exceptions for reserved names such as rowid. Sqlite rtrees require that your columns must be a even list, each pair corresponding to a dimension of your geometrical index (eg. [minX, maxX, minY, maxY]). Sqlite allows the dimension to vary between 1 and 5.
`handler`	The block (and blockType) that handles extracting rtree index information from a row in the database.


                    
                    
                    -initWithSetup:handler:versionTag:

Creates a new rtree index extension. After creation, you’ll need to register the extension with the database system.

See

YapDatabaseRTreeIndexSetup

See

YapDatabaseRTreeIndexHandler

See

YapDatabase registerExtension:withName:

Declaration

Objective-C

- (id)initWithSetup:(YapDatabaseRTreeIndexSetup *)setup
            handler:(YapDatabaseRTreeIndexHandler *)handler
         versionTag:(NSString *)versionTag;

Swift

init!(setup: YapDatabaseRTreeIndexSetup!, handler: YapDatabaseRTreeIndexHandler!, versionTag: String!)

Parameters

`setup`	A YapDatabaseRTreeIndexSetup instance allows you to specify the column names. The column names can be whatever you want, with a few exceptions for reserved names such as rowid. Sqlite rtrees require that your columns must be a even list, each pair corresponding to a dimension of your geometrical index (eg. [minX, maxX, minY, maxY]). Sqlite allows the dimension to vary between 1 and 5.
`handler`	The block (and blockType) that handles extracting secondary index information from a row in the database.
`versionTag`	If, after creating the rtree index, you need to change the setup or block, then simply increment the version parameter. If you pass a version that is different from the last initialization of the extension, then it will automatically re-create itself.


                    
                    
                    -initWithSetup:handler:versionTag:options:

Creates a new rtree index extension. After creation, you’ll need to register the extension with the database system.

See

YapDatabaseRTreeIndexSetup

See

YapDatabaseRTreeIndexHandler

See

YapDatabase registerExtension:withName:

Declaration

Objective-C

- (id)initWithSetup:(YapDatabaseRTreeIndexSetup *)setup
            handler:(YapDatabaseRTreeIndexHandler *)handler
         versionTag:(NSString *)versionTag
            options:(YapDatabaseRTreeIndexOptions *)options;

Swift

init!(setup: YapDatabaseRTreeIndexSetup!, handler: YapDatabaseRTreeIndexHandler!, versionTag: String!, options: YapDatabaseRTreeIndexOptions!)

Parameters

`setup`	A YapDatabaseRTreeIndexSetup instance allows you to specify the column names. The column names can be whatever you want, with a few exceptions for reserved names such as rowid. Sqlite rtrees require that your columns must be a even list, each pair corresponding to a dimension of your geometrical index (eg. [minX, maxX, minY, maxY]). Sqlite allows the dimension to vary between 1 and 5.
`handler`	The block (and blockType) that handles extracting secondary index information from a row in the database.
`versionTag`	If, after creating the rtree index, you need to change the setup or block, then simply increment the version parameter. If you pass a version that is different from the last initialization of the extension, then it will automatically re-create itself.
`options`	Allows you to specify extra options to configure the extension. See the YapDatabaseRTreeIndexOptions class for more information.


                    
                    
                    setup

Undocumented

Declaration

Objective-C

@property (nonatomic, copy, readonly) YapDatabaseRTreeIndexSetup *setup

Swift

@NSCopying var setup: YapDatabaseRTreeIndexSetup! { get }


                    
                    
                    handler

Undocumented

Declaration

Objective-C

@property (nonatomic, strong, readonly) YapDatabaseRTreeIndexHandler *handler

Swift

var handler: YapDatabaseRTreeIndexHandler! { get }

versionTag
The versionTag assists in making changes to the extension.

If you need to change the columnNames and/or block, then simply pass a different versionTag during the init method, and the extension will automatically update itself.
Declaration
Objective-C

@property (readonly, copy, nonatomic) NSString *versionTag;
Swift

var versionTag: String! { get }