/django/contrib/gis/db/backends/oracle/operations.py
https://code.google.com/p/mango-py/ · Python · 293 lines · 248 code · 21 blank · 24 comment · 13 complexity · 0c4e7b51f1aa50f30bdc4ea2deb3f5e0 MD5 · raw file
- """
- 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.backends.oracle.base import DatabaseOperations
- from django.contrib.gis.db.backends.base import BaseSpatialOperations
- from django.contrib.gis.db.backends.oracle.adapter import OracleSpatialAdapter
- from django.contrib.gis.db.backends.util import SpatialFunction
- from django.contrib.gis.geometry.backend import Geometry
- from django.contrib.gis.measure import Distance
- class SDOOperation(SpatialFunction):
- "Base class for SDO* Oracle operations."
- sql_template = "%(function)s(%(geo_col)s, %(geometry)s) %(operator)s '%(result)s'"
- def __init__(self, func, **kwargs):
- kwargs.setdefault('operator', '=')
- kwargs.setdefault('result', 'TRUE')
- super(SDOOperation, self).__init__(func, **kwargs)
- class SDODistance(SpatialFunction):
- "Class for Distance queries."
- sql_template = ('%(function)s(%(geo_col)s, %(geometry)s, %(tolerance)s) '
- '%(operator)s %(result)s')
- dist_func = 'SDO_GEOM.SDO_DISTANCE'
- def __init__(self, op, tolerance=0.05):
- super(SDODistance, self).__init__(self.dist_func,
- tolerance=tolerance,
- operator=op, result='%s')
- class SDODWithin(SpatialFunction):
- dwithin_func = 'SDO_WITHIN_DISTANCE'
- sql_template = "%(function)s(%(geo_col)s, %(geometry)s, %%s) = 'TRUE'"
- def __init__(self):
- super(SDODWithin, self).__init__(self.dwithin_func)
- class SDOGeomRelate(SpatialFunction):
- "Class for using SDO_GEOM.RELATE."
- relate_func = 'SDO_GEOM.RELATE'
- sql_template = ("%(function)s(%(geo_col)s, '%(mask)s', %(geometry)s, "
- "%(tolerance)s) %(operator)s '%(mask)s'")
- 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').
- super(SDOGeomRelate, self).__init__(self.relate_func, operator='=',
- mask=mask, tolerance=tolerance)
- 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)
- sql_template = "%(function)s(%(geo_col)s, %(geometry)s, 'mask=%(mask)s') = 'TRUE'"
- relate_func = 'SDO_RELATE'
- def __init__(self, mask):
- if not self.mask_regex.match(mask):
- raise ValueError('Invalid %s mask: "%s"' % (self.relate_func, mask))
- super(SDORelate, self).__init__(self.relate_func, mask=mask)
- # Valid distance types and substitutions
- dtypes = (Decimal, Distance, float, int, long)
- class OracleOperations(DatabaseOperations, BaseSpatialOperations):
- compiler_module = "django.contrib.gis.db.backends.oracle.compiler"
- name = 'oracle'
- oracle = True
- valid_aggregates = dict([(a, None) for a in ('Union', 'Extent')])
- Adapter = OracleSpatialAdapter
- Adaptor = Adapter # Backwards-compatibility alias.
- area = 'SDO_GEOM.SDO_AREA'
- gml= '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'
- perimeter = length
- point_on_surface = 'SDO_GEOM.SDO_POINTONSURFACE'
- reverse = 'SDO_UTIL.REVERSE_LINESTRING'
- 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 =)
- select = 'SDO_UTIL.TO_WKTGEOMETRY(%s)'
- distance_functions = {
- 'distance_gt' : (SDODistance('>'), dtypes),
- 'distance_gte' : (SDODistance('>='), dtypes),
- 'distance_lt' : (SDODistance('<'), dtypes),
- 'distance_lte' : (SDODistance('<='), dtypes),
- 'dwithin' : (SDODWithin(), dtypes),
- }
- 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'),
- }
- geometry_functions.update(distance_functions)
- gis_terms = ['isnull']
- gis_terms += geometry_functions.keys()
- gis_terms = dict([(term, None) for term in gis_terms])
- truncate_params = {'relate' : None}
- def __init__(self, connection):
- super(OracleOperations, self).__init__()
- self.connection = connection
- def convert_extent(self, clob):
- if clob:
- # Generally, Oracle returns a polygon for the extent -- however,
- # it can return a single point if there's only one Point in the
- # table.
- ext_geom = Geometry(clob.read())
- gtype = str(ext_geom.geom_type)
- if gtype == 'Polygon':
- # Construct the 4-tuple from the coordinates in the polygon.
- shell = ext_geom.shell
- ll, ur = shell[0][:2], shell[2][:2]
- elif gtype == 'Point':
- ll = ext_geom.coords[:2]
- ur = ll
- else:
- raise Exception('Unexpected geometry type returned for extent: %s' % gtype)
- xmin, ymin = ll
- xmax, ymax = ur
- return (xmin, ymin, xmax, ymax)
- else:
- return None
- def convert_geom(self, clob, geo_field):
- if clob:
- return Geometry(clob.read(), geo_field.srid)
- else:
- return None
- def geo_db_type(self, f):
- """
- Returns the geometry database type for Oracle. Unlike other spatial
- backends, no stored procedure is necessary and it's the same for all
- geometry types.
- """
- return 'MDSYS.SDO_GEOMETRY'
- def get_distance(self, f, value, lookup_type):
- """
- Returns the distance parameters given the value and the lookup type.
- On Oracle, geometry columns with a geodetic coordinate system behave
- implicitly like a geography column, and thus meters will be used as
- the distance parameter on them.
- """
- if not value:
- return []
- value = value[0]
- if isinstance(value, Distance):
- if f.geodetic(self.connection):
- dist_param = value.m
- else:
- dist_param = getattr(value, Distance.unit_attname(f.units_name(self.connection)))
- else:
- dist_param = value
- # dwithin lookups on oracle require a special string parameter
- # that starts with "distance=".
- if lookup_type == 'dwithin':
- dist_param = 'distance=%s' % dist_param
- return [dist_param]
- def get_geom_placeholder(self, f, 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 'NULL'
- def transform_value(val, srid):
- return val.srid != srid
- if hasattr(value, 'expression'):
- if transform_value(value, f.srid):
- placeholder = '%s(%%s, %s)' % (self.transform, f.srid)
- else:
- placeholder = '%s'
- # No geometry value used for F expression, substitue in
- # the column name instead.
- return placeholder % '%s.%s' % tuple(map(self.quote_name, value.cols[value.expression]))
- else:
- if transform_value(value, f.srid):
- return '%s(SDO_GEOMETRY(%%s, %s), %s)' % (self.transform, value.srid, f.srid)
- else:
- return 'SDO_GEOMETRY(%%s, %s)' % f.srid
- def spatial_lookup_sql(self, lvalue, lookup_type, value, field, qn):
- "Returns the SQL WHERE clause for use in Oracle spatial SQL construction."
- alias, col, db_type = lvalue
- # Getting the quoted table name as `geo_col`.
- geo_col = '%s.%s' % (qn(alias), qn(col))
- # See if a Oracle Geometry function matches the lookup type next
- lookup_info = self.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
- geom = value[0]
- # Ensuring that a tuple _value_ was passed in from the user
- if not isinstance(value, tuple):
- raise ValueError('Tuple required for `%s` lookup type.' % lookup_type)
- if len(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(value[1], arg_type):
- raise ValueError('Argument type should be %s, got %s instead.' % (arg_type, type(value[1])))
- if lookup_type == 'relate':
- # The SDORelate class handles construction for these queries,
- # and verifies the mask argument.
- return sdo_op(value[1]).as_sql(geo_col, self.get_geom_placeholder(field, geom))
- else:
- # Otherwise, just call the `as_sql` method on the SDOOperation instance.
- return sdo_op.as_sql(geo_col, self.get_geom_placeholder(field, geom))
- 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, self.get_geom_placeholder(field, value))
- elif lookup_type == 'isnull':
- # Handling 'isnull' lookup type
- return "%s IS %sNULL" % (geo_col, (not value and 'NOT ' or ''))
- raise TypeError("Got invalid lookup_type: %s" % repr(lookup_type))
- def spatial_aggregate_sql(self, agg):
- """
- Returns the spatial aggregate SQL template and function for the
- given Aggregate instance.
- """
- agg_name = agg.__class__.__name__.lower()
- if agg_name == 'union' : agg_name += 'agg'
- if agg.is_extent:
- sql_template = '%(function)s(%(field)s)'
- else:
- sql_template = '%(function)s(SDOAGGRTYPE(%(field)s,%(tolerance)s))'
- sql_function = getattr(self, agg_name)
- return self.select % sql_template, sql_function
- # Routines for getting the OGC-compliant models.
- def geometry_columns(self):
- from django.contrib.gis.db.backends.oracle.models import GeometryColumns
- return GeometryColumns
- def spatial_ref_sys(self):
- from django.contrib.gis.db.backends.oracle.models import SpatialRefSys
- return SpatialRefSys