wrong result in spatial data query sql server

0
votes

Im trying to get familiar with spatial data using sql server 2008.

I use book: http://www.beginningspatial.com/

and there is sample data: http://www.census.gov/geo/cob/bdy/zt/z500shp/zt06_d00_shp.zip

I uploaded it to my sql server database and Spatial results are presented well. Everything seems to be ok but when I tried to calculate distance between 2 geometries result is really small.

For example 0.27

The same is if I try to calculate STLength of given region. Result also is very small like 0.19 for example.

I wonder why the results are so small. I used SRID 4269 importing data.

Does anyone have any idea why is it like that ? I think that the result whould be in meters.

Thanks for any advice

1
sql-server-2008geospatialspatial

1 Answers

1
votes

STLength returns units in the data source's unit of measure. In your case, you chose SRID 4326, which stores the data in latitude/longitude, therefore your base units are a "degree", not a standard linear unit like feet/meters. To calculate the distance in linear units, you should load your data as a projected format.

You might want to refer to this very similar question, as well.