Equivalent function for box3d which available in Postgis

Question

I have a road_network data I am trying to
obtain all the values within a bounding box formed by lat long values,
i tried below example but it compiled and produces some error 
declare @exmp varchar;
set @exmp = 'POLYGON(81.959545899804 25.243612186501,81.985879306176 25.2726072490010)'
DECLARE @box geography = geography::STLineFromText(@exmp, 4326)
SELECT source,target,geog4326.STAsText()
FROM road_network
WHERE geog4326.STIntersects(@box) = 1;
in PostGIS theres a box3d, i like to know is there any equivalent function available in MS SQL Server ?

Answer 1

a few problems here:
1.
run this- what do you see?
declare @exmp varchar;
set @exmp
= 'POLYGON(81.959545899804 25.243612186501,81.985879306176 25.2726072490010)'
print @exmp
a varchar initialised without a size defaults to varchar(1)
so set varchar to the required value or set it to varchar(max)
2. A polygon requires at least 3 distinct points and the start and end points need to be the same. I'm assuming you just want to draw a line between the 1st & 3rd points of your bounding box and have the db engine draw the box around them. So you should
be declaring it as a LINESTRING, not a polygon. Unfortunately geography doesn't have a .STEnvelope() function, so you'll need to convert the line to geometry, get the envelope, then convert back
declare @exmp varchar(max);
set @exmp = 'LINESTRING(81.959545899804 25.243612186501, 81.985879306176 25.2726072490010)'
DECLARE @box geography = geography::STLineFromText(@exmp, 4326)
-- Work out bounding box by converting to geometry via WKB, then using STEnvelope()
DECLARE @boundingbox geometry = geometry::STGeomFromWKB(@box.STAsBinary(), @box.STSrid).STEnvelope();
-- Convert result back to geography via WKB
SET @box = geography::STGeomFromWKB(@boundingbox.STAsBinary(), @boundingbox.STSrid);
(from
http://social.msdn.microsoft.com/Forums/sqlserver/en-US/453d2fe8-bbe6-4047-90ce-556015c17e64/how-to-get-the-bounding-rectangle-of-a-geography)
now you can intersect your @box.
If this were geometry you could've just used .STFilter() on your linestring directly.. I'm not sure how .Filter() works with geography but investigate it as it'll be faster if your road_network table has correct spatial indexes.
Jakub @ Adelaide, Australia