Any record which inherits from this TSQLRecordRTree class must have only sftFloat (i.e. Delphi double) published fields, grouped by pairs, each as minimum- and maximum-value, up to 5 dimensions (i.e. 11 columns, including the ID property). 

Its ID: integer property must be set before adding a TSQLRecordRTree to the database, e.g. to link an R-Tree representation to a regular TSQLRecord table containing the main data.

Queries against the ID or the coordinate ranges are almost immediate: so you can e.g. extract some coordinates box from the main regular TSQLRecord table, then use a TSQLRecordRTree-joined query to make the process faster; this is exactly what the TSQLRestClient. RTreeMatch method offers: for instance, running with aMapData. BlobField filled with [-81,-79.6,35,36.2] the following lines:

 aClient.RTreeMatch(TSQLRecordMapData,'BlobField',TSQLRecordMapBox,
   aMapData.BlobField,ResultID);

will execute the following SQL statement:

 SELECT MapData.ID From MapData, MapBox WHERE MapData.ID=MapBox.ID
AND minX>=:(-81.0): AND maxX<=:(-79.6): AND minY>=:(35.0): AND :(maxY<=36.2):
AND MapBox_in(MapData.BlobField,:('\uFFF0base64encoded-81,-79.6,35,36.2'):);

The MapBox_in SQL function is registered in TSQLRestServerDB. Create constructor for all TSQLRecordRTree classes of the current database model. Both BlobToCoord and ContainedIn class methods are used to handle the box storage in the BLOB. 

By default, it will process a raw array of double, with a default box match (that is ContainedIn method will match the simple minX>=...maxY<=... where clause).

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