MySQL does not yet implement the following GIS features:
Additional Metadata Views
OpenGIS specifications propose several additional metadata views. For example, a system view named
GEOMETRY_COLUMNS contains a description of geometry columns, one row
for each geometry column in the database.
The problem is that there is an existing SQL function
Length() that calculates the length of string values, and sometimes
it is not possible to distinguish whether the function is called in a textual or spatial context. We
need either to solve this somehow, or decide on another function name.