[postgis-users] Count the number of times a geometry crosses another

[Matt McClelland]

Hi All

I am building a map useing two separate creek data sets (OSM creeks and DEM
derived creeks).  The OSM data is much better especially where the rivers
are in flat country.

I am wanting to find all the creeks in the DEM dataset that are already in
the OSM (so they can be deleted).
I am happy to delete a DEM creek if it is crosses an OSM creek twice to
more times (if it crosses just once then it is more likely a side creek)

Is there a function like "ST_Crosses" that returns a count of the number of
times a geometry is crossed?  Or any other better ideas on how to determine
duplicate creeks?
I have attached an image to show the issue.  Light blue are OSM creeks and
dark blue are DEM derived creeks

Thanks

Matt  :)
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