Foreign Data Wrapper Handler

Can anyone recommend a good online resource for learning how to set up a 
foreign data wrapper using a custom fdw name?  It seems the trick is to 
use a handler to make it work but so far the search results have been 
elusive for creating a fdw with a successful outcome.

I'm using 'PostgreSQL 11.8 on amd64-portbld-freebsd12.1, compiled by 
FreeBSD clang version 8.0.1 (tags/RELEASE_801/final 366581) (based on 
LLVM 8.0.1), 64-bit'

Thanks for your help!

Sue

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Susan E Hurst
Principal Consultant
Brookhurst Data LLC
Email: susan.hurst@brookhurstdata.com
Mobile: 314-486-3261