Documentation Home
MySQL 5.5 Reference Manual
Related Documentation Download this Manual Excerpts from this Manual

MySQL 5.5 Reference Manual  /  ...  /  Optimizing Spatial Analysis Optimizing Spatial Analysis

For MyISAM tables, search operations in columns containing spatial data can be optimized using SPATIAL indexes. The most typical operations 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 for SPATIAL indexes on spatial columns. A SPATIAL index is built using the minimum bounding rectangle (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.

It is also possible to create normal indexes on spatial columns. In a non-SPATIAL index, you must declare a prefix for any spatial column except for POINT columns.

MyISAM supports both SPATIAL and non-SPATIAL indexes. Other storage engines support non-SPATIAL indexes, as described in Section 13.1.13, “CREATE INDEX Syntax”.

Download this Manual
User Comments
Sign Up Login You must be logged in to post a comment.