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diff --git a/webapp/django/contrib/gis/db/backend/oracle/query.py b/webapp/django/contrib/gis/db/backend/oracle/query.py
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+"""
+ This module contains the spatial lookup types, and the `get_geo_where_clause`
+ routine for Oracle Spatial.
+
+ Please note that WKT support is broken on the XE version, and thus
+ this backend will not work on such platforms.  Specifically, XE lacks 
+ support for an internal JVM, and Java libraries are required to use 
+ the WKT constructors.
+"""
+import re
+from decimal import Decimal
+from django.db import connection
+from django.contrib.gis.db.backend.util import SpatialFunction
+from django.contrib.gis.measure import Distance
+qn = connection.ops.quote_name
+
+# The GML, distance, transform, and union procedures.
+AREA = 'SDO_GEOM.SDO_AREA'
+ASGML = 'SDO_UTIL.TO_GMLGEOMETRY'
+CENTROID = 'SDO_GEOM.SDO_CENTROID'
+DIFFERENCE = 'SDO_GEOM.SDO_DIFFERENCE'
+DISTANCE = 'SDO_GEOM.SDO_DISTANCE'
+EXTENT = 'SDO_AGGR_MBR'
+INTERSECTION = 'SDO_GEOM.SDO_INTERSECTION'
+LENGTH = 'SDO_GEOM.SDO_LENGTH'
+NUM_GEOM = 'SDO_UTIL.GETNUMELEM'
+NUM_POINTS = 'SDO_UTIL.GETNUMVERTICES'
+POINT_ON_SURFACE = 'SDO_GEOM.SDO_POINTONSURFACE'
+SYM_DIFFERENCE = 'SDO_GEOM.SDO_XOR'
+TRANSFORM = 'SDO_CS.TRANSFORM'
+UNION = 'SDO_GEOM.SDO_UNION'
+UNIONAGG = 'SDO_AGGR_UNION'
+
+# We want to get SDO Geometries as WKT because it is much easier to 
+# instantiate GEOS proxies from WKT than SDO_GEOMETRY(...) strings.  
+# However, this adversely affects performance (i.e., Java is called 
+# to convert to WKT on every query).  If someone wishes to write a 
+# SDO_GEOMETRY(...) parser in Python, let me know =)
+GEOM_SELECT = 'SDO_UTIL.TO_WKTGEOMETRY(%s)'
+
+#### Classes used in constructing Oracle spatial SQL ####
+class SDOOperation(SpatialFunction):
+    "Base class for SDO* Oracle operations."
+    def __init__(self, func, **kwargs):
+        kwargs.setdefault('operator', '=')
+        kwargs.setdefault('result', 'TRUE')
+        kwargs.setdefault('end_subst', ") %s '%s'")
+        super(SDOOperation, self).__init__(func, **kwargs)
+
+class SDODistance(SpatialFunction):
+    "Class for Distance queries."
+    def __init__(self, op, tolerance=0.05):
+        super(SDODistance, self).__init__(DISTANCE, end_subst=', %s) %%s %%s' % tolerance, 
+                                          operator=op, result='%%s')
+
+class SDOGeomRelate(SpatialFunction):
+    "Class for using SDO_GEOM.RELATE."
+    def __init__(self, mask, tolerance=0.05):
+        # SDO_GEOM.RELATE(...) has a peculiar argument order: column, mask, geom, tolerance.
+        # Moreover, the runction result is the mask (e.g., 'DISJOINT' instead of 'TRUE').
+        end_subst = "%s%s) %s '%s'" % (', %%s, ', tolerance, '=', mask)
+        beg_subst = "%%s(%%s, '%s'" % mask 
+        super(SDOGeomRelate, self).__init__('SDO_GEOM.RELATE', beg_subst=beg_subst, end_subst=end_subst)
+
+class SDORelate(SpatialFunction):
+    "Class for using SDO_RELATE."
+    masks = 'TOUCH|OVERLAPBDYDISJOINT|OVERLAPBDYINTERSECT|EQUAL|INSIDE|COVEREDBY|CONTAINS|COVERS|ANYINTERACT|ON'
+    mask_regex = re.compile(r'^(%s)(\+(%s))*$' % (masks, masks), re.I)
+    def __init__(self, mask):
+        func = 'SDO_RELATE'
+        if not self.mask_regex.match(mask):
+            raise ValueError('Invalid %s mask: "%s"' % (func, mask))
+        super(SDORelate, self).__init__(func, end_subst=", 'mask=%s') = 'TRUE'" % mask)
+
+#### Lookup type mapping dictionaries of Oracle spatial operations ####
+
+# Valid distance types and substitutions
+dtypes = (Decimal, Distance, float, int, long)
+DISTANCE_FUNCTIONS = {
+    'distance_gt' : (SDODistance('>'), dtypes),
+    'distance_gte' : (SDODistance('>='), dtypes),
+    'distance_lt' : (SDODistance('<'), dtypes),
+    'distance_lte' : (SDODistance('<='), dtypes),
+    'dwithin' : (SDOOperation('SDO_WITHIN_DISTANCE', 
+                              beg_subst="%s(%s, %%s, 'distance=%%s'"), dtypes),
+    }
+
+ORACLE_GEOMETRY_FUNCTIONS = {
+    'contains' : SDOOperation('SDO_CONTAINS'),
+    'coveredby' : SDOOperation('SDO_COVEREDBY'),
+    'covers' : SDOOperation('SDO_COVERS'),
+    'disjoint' : SDOGeomRelate('DISJOINT'),
+    'intersects' : SDOOperation('SDO_OVERLAPBDYINTERSECT'), # TODO: Is this really the same as ST_Intersects()?
+    'equals' : SDOOperation('SDO_EQUAL'),
+    'exact' : SDOOperation('SDO_EQUAL'),
+    'overlaps' : SDOOperation('SDO_OVERLAPS'),
+    'same_as' : SDOOperation('SDO_EQUAL'),
+    'relate' : (SDORelate, basestring), # Oracle uses a different syntax, e.g., 'mask=inside+touch'
+    'touches' : SDOOperation('SDO_TOUCH'),
+    'within' : SDOOperation('SDO_INSIDE'),
+    }
+ORACLE_GEOMETRY_FUNCTIONS.update(DISTANCE_FUNCTIONS)
+
+# This lookup type does not require a mapping.
+MISC_TERMS = ['isnull']
+
+# Acceptable lookup types for Oracle spatial.
+ORACLE_SPATIAL_TERMS  = ORACLE_GEOMETRY_FUNCTIONS.keys()
+ORACLE_SPATIAL_TERMS += MISC_TERMS
+ORACLE_SPATIAL_TERMS = dict((term, None) for term in ORACLE_SPATIAL_TERMS) # Making dictionary for fast lookups
+
+#### The `get_geo_where_clause` function for Oracle ####
+def get_geo_where_clause(table_alias, name, lookup_type, geo_annot):
+    "Returns the SQL WHERE clause for use in Oracle spatial SQL construction."
+    # Getting the quoted table name as `geo_col`.
+    geo_col = '%s.%s' % (qn(table_alias), qn(name))
+
+    # See if a Oracle Geometry function matches the lookup type next
+    lookup_info = ORACLE_GEOMETRY_FUNCTIONS.get(lookup_type, False)
+    if lookup_info:
+        # Lookup types that are tuples take tuple arguments, e.g., 'relate' and 
+        # 'dwithin' lookup types.
+        if isinstance(lookup_info, tuple):
+            # First element of tuple is lookup type, second element is the type
+            # of the expected argument (e.g., str, float)
+            sdo_op, arg_type = lookup_info
+
+            # Ensuring that a tuple _value_ was passed in from the user
+            if not isinstance(geo_annot.value, tuple):
+                raise TypeError('Tuple required for `%s` lookup type.' % lookup_type)
+            if len(geo_annot.value) != 2: 
+                raise ValueError('2-element tuple required for %s lookup type.' % lookup_type)
+            
+            # Ensuring the argument type matches what we expect.
+            if not isinstance(geo_annot.value[1], arg_type):
+                raise TypeError('Argument type should be %s, got %s instead.' % (arg_type, type(geo_annot.value[1])))
+
+            if lookup_type == 'relate':
+                # The SDORelate class handles construction for these queries, 
+                # and verifies the mask argument.
+                return sdo_op(geo_annot.value[1]).as_sql(geo_col)
+            else:
+                # Otherwise, just call the `as_sql` method on the SDOOperation instance.
+                return sdo_op.as_sql(geo_col)
+        else:
+            # Lookup info is a SDOOperation instance, whose `as_sql` method returns
+            # the SQL necessary for the geometry function call. For example:  
+            #  SDO_CONTAINS("geoapp_country"."poly", SDO_GEOMTRY('POINT(5 23)', 4326)) = 'TRUE'
+            return lookup_info.as_sql(geo_col)
+    elif lookup_type == 'isnull':
+        # Handling 'isnull' lookup type
+        return "%s IS %sNULL" % (geo_col, (not geo_annot.value and 'NOT ' or ''))
+
+    raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type))