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diff --git a/webapp/django/contrib/gis/db/backend/oracle/field.py b/webapp/django/contrib/gis/db/backend/oracle/field.py
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+++ b/webapp/django/contrib/gis/db/backend/oracle/field.py
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+from django.db import connection
+from django.db.backends.util import truncate_name
+from django.db.models.fields import Field # Django base Field class
+from django.contrib.gis.db.backend.util import gqn
+from django.contrib.gis.db.backend.oracle.query import TRANSFORM
+
+# Quotename & geographic quotename, respectively.
+qn = connection.ops.quote_name
+
+class OracleSpatialField(Field):
+ """
+ The backend-specific geographic field for Oracle Spatial.
+ """
+
+ empty_strings_allowed = False
+
+ def __init__(self, extent=(-180.0, -90.0, 180.0, 90.0), tolerance=0.05, **kwargs):
+ """
+ Oracle Spatial backend needs to have the extent -- for projected coordinate
+ systems _you must define the extent manually_, since the coordinates are
+ for geodetic systems. The `tolerance` keyword specifies the tolerance
+ for error (in meters), and defaults to 0.05 (5 centimeters).
+ """
+ # Oracle Spatial specific keyword arguments.
+ self._extent = extent
+ self._tolerance = tolerance
+ # Calling the Django field initialization.
+ super(OracleSpatialField, self).__init__(**kwargs)
+
+ def _add_geom(self, style, db_table):
+ """
+ Adds this geometry column into the Oracle USER_SDO_GEOM_METADATA
+ table.
+ """
+
+ # Checking the dimensions.
+ # TODO: Add support for 3D geometries.
+ if self._dim != 2:
+ raise Exception('3D geometries not yet supported on Oracle Spatial backend.')
+
+ # Constructing the SQL that will be used to insert information about
+ # the geometry column into the USER_GSDO_GEOM_METADATA table.
+ meta_sql = style.SQL_KEYWORD('INSERT INTO ') + \
+ style.SQL_TABLE('USER_SDO_GEOM_METADATA') + \
+ ' (%s, %s, %s, %s)\n ' % tuple(map(qn, ['TABLE_NAME', 'COLUMN_NAME', 'DIMINFO', 'SRID'])) + \
+ style.SQL_KEYWORD(' VALUES ') + '(\n ' + \
+ style.SQL_TABLE(gqn(db_table)) + ',\n ' + \
+ style.SQL_FIELD(gqn(self.column)) + ',\n ' + \
+ style.SQL_KEYWORD("MDSYS.SDO_DIM_ARRAY") + '(\n ' + \
+ style.SQL_KEYWORD("MDSYS.SDO_DIM_ELEMENT") + \
+ ("('LONG', %s, %s, %s),\n " % (self._extent[0], self._extent[2], self._tolerance)) + \
+ style.SQL_KEYWORD("MDSYS.SDO_DIM_ELEMENT") + \
+ ("('LAT', %s, %s, %s)\n ),\n" % (self._extent[1], self._extent[3], self._tolerance)) + \
+ ' %s\n );' % self._srid
+ return meta_sql
+
+ def _geom_index(self, style, db_table):
+ "Creates an Oracle Geometry index (R-tree) for this geometry field."
+
+ # Getting the index name, Oracle doesn't allow object
+ # names > 30 characters.
+ idx_name = truncate_name('%s_%s_id' % (db_table, self.column), 30)
+
+ sql = style.SQL_KEYWORD('CREATE INDEX ') + \
+ style.SQL_TABLE(qn(idx_name)) + \
+ style.SQL_KEYWORD(' ON ') + \
+ style.SQL_TABLE(qn(db_table)) + '(' + \
+ style.SQL_FIELD(qn(self.column)) + ') ' + \
+ style.SQL_KEYWORD('INDEXTYPE IS ') + \
+ style.SQL_TABLE('MDSYS.SPATIAL_INDEX') + ';'
+ return sql
+
+ def post_create_sql(self, style, db_table):
+ """
+ Returns SQL that will be executed after the model has been
+ created.
+ """
+ # Getting the meta geometry information.
+ post_sql = self._add_geom(style, db_table)
+
+ # Getting the geometric index for this Geometry column.
+ if self._index:
+ return (post_sql, self._geom_index(style, db_table))
+ else:
+ return (post_sql,)
+
+ def db_type(self):
+ "The Oracle geometric data type is MDSYS.SDO_GEOMETRY."
+ return 'MDSYS.SDO_GEOMETRY'
+
+ def get_placeholder(self, value):
+ """
+ Provides a proper substitution value for Geometries that are not in the
+ SRID of the field. Specifically, this routine will substitute in the
+ SDO_CS.TRANSFORM() function call.
+ """
+ if value is None:
+ return '%s'
+ elif value.srid != self._srid:
+ # Adding Transform() to the SQL placeholder.
+ return '%s(SDO_GEOMETRY(%%s, %s), %s)' % (TRANSFORM, value.srid, self._srid)
+ else:
+ return 'SDO_GEOMETRY(%%s, %s)' % self._srid