GeoSpatial Queries
Posted: Mon 12 Mar 2012 16:35
We have a 21 million table in PostGIS database. The fields are all simple text except for one geometry field (a simple Polygon rectangle which is a bounding box.
We typically do just read queries of the form:
Now that we bought DotConnect Pro, I want to do this query from C# (an WCF application).
I am a newbie with DotConnect, I have read your blog post:
http://www.devart.com/blogs/dotconnect/ ... ework.html
But it seems to me that this is not what we are looking for. First, the users are saying that the code is out of date. Secondly, it seems that there is NO reason to try to do the spatial intersect in LINQ.
Would it not make more sense to pass in the query rectangle to a stored procedure in the PostGreSQL DB, and then just return the text columns? We can then do additional LINQ style filtering.
But the fact that we have 21 million records (GIST indexed) means that for performance reasons we want to use the native geospatial power of PostGIS and not sharpMap or other spatial libraries .
Can anyone point me to examples of trying to expose stored procedures like the above to dotConnect?
We typically do just read queries of the form:
Code: Select all
SELECT *
FROM portal.metadata as cat
WHERE ST_Intersects(ST_GeomFromText('POLYGON((-70 42,-71 42,-71 41,-70 41,-70 42))', 4326), cat.location);
I am a newbie with DotConnect, I have read your blog post:
http://www.devart.com/blogs/dotconnect/ ... ework.html
But it seems to me that this is not what we are looking for. First, the users are saying that the code is out of date. Secondly, it seems that there is NO reason to try to do the spatial intersect in LINQ.
Would it not make more sense to pass in the query rectangle to a stored procedure in the PostGreSQL DB, and then just return the text columns? We can then do additional LINQ style filtering.
But the fact that we have 21 million records (GIST indexed) means that for performance reasons we want to use the native geospatial power of PostGIS and not sharpMap or other spatial libraries .
Can anyone point me to examples of trying to expose stored procedures like the above to dotConnect?