/django/contrib/gis/db/backends/mysql/introspection.py

 1from MySQLdb.constants import FIELD_TYPE
 2
 3from django.contrib.gis.gdal import OGRGeomType
 4from django.db.backends.mysql.introspection import DatabaseIntrospection
 5
 6class MySQLIntrospection(DatabaseIntrospection):
 7    # Updating the data_types_reverse dictionary with the appropriate
 8    # type for Geometry fields.
 9    data_types_reverse = DatabaseIntrospection.data_types_reverse.copy()
10    data_types_reverse[FIELD_TYPE.GEOMETRY] = 'GeometryField'
11
12    def get_geometry_type(self, table_name, geo_col):
13        cursor = self.connection.cursor()
14        try:
15            # In order to get the specific geometry type of the field,
16            # we introspect on the table definition using `DESCRIBE`.
17            cursor.execute('DESCRIBE %s' %
18                           self.connection.ops.quote_name(table_name))
19            # Increment over description info until we get to the geometry
20            # column.
21            for column, typ, null, key, default, extra in cursor.fetchall():
22                if column == geo_col:
23                    # Using OGRGeomType to convert from OGC name to Django field.
24                    # MySQL does not support 3D or SRIDs, so the field params
25                    # are empty.
26                    field_type = OGRGeomType(typ).django
27                    field_params = {}
28                    break
29        finally:
30            cursor.close()
31
32        return field_type, field_params