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(mysql.info.gz) Optimizing spatial analysis

Info Catalog (mysql.info.gz) Analysing spatial information (mysql.info.gz) Spatial extensions in MySQL (mysql.info.gz) MySQL GIS conformance and compatibility
 
 18.6 Optimizing Spatial Analysis
 ================================
 
 Search operations in non-spatial databases can be optimized using
 indexes. This is true for spatial databases as well.  With the help of
 a great variety of multi-dimensional indexing methods that have
 previously been designed, it is possible to optimize spatial searches.
 The most typical of these are:
 
    * Point queries that search for all objects that contain a given
      point
 
    * Region queries that search for all objects that overlap a given
      region
 
 
 MySQL uses *R-Trees with quadratic splitting* to index spatial columns.
 A spatial index is built using the MBR of a geometry.  For most
 geometries, the MBR is a minimum rectangle that surrounds the
 geometries. For a horizontal or a vertical linestring, the MBR is a
 rectangle degenerated into the linestring.  For a point, the MBR is a
 rectangle degenerated into the point.
 

Menu

 
* Creating spatial indexes    Creating Spatial Indexes
* Using a spatial index       Using a Spatial Index
 
Info Catalog (mysql.info.gz) Analysing spatial information (mysql.info.gz) Spatial extensions in MySQL (mysql.info.gz) MySQL GIS conformance and compatibility
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