sql - points within a particular distance -



sql - points within a particular distance -

i have table conatining set of points. create query checks distance between points , if distance little er tolerance set points one.

any suggestions how can accomplish such task?

the next graphical issue of have. want 1 point exist 3 distinct roads meet

this tricky issue more 1 way prepare it.

one obvious strategy seek , find unique points snapped virtual grid, using st_snaptogrid. technique works best projected units (e.g., metres utm), not geographic coordinates (with degrees of latitude/longitude), have variable physical distances.

sql postgresql geospatial postgis spatial-query

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