i have table with latitude & longitude columns in sql. how can i select all records with lat-long 60 degree north> ( Arctic Region )
Thanks Pragnesh
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i have table with latitude & longitude columns in sql. how can i select all records with lat-long 60 degree north> ( Arctic Region ) Thanks Pragnesh |
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One thing to consider is that if you have a large dataset then defining your data using lat / long, instead of using a real GIS geometry like PostGIS geography or geometry, prevents you from building spatial indexes on your data. You could get by with building a B+-tree index on your latitude field for the query iant provided, but the moment you need to start doing queries involving both longitude and latitude your indexes will perform sub-par (even if you have two separate indexes on both lat and lon). |
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how about:
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