Queries on Vacuum

 I am (slowly) adding handy PostgreSQL queries to my GitHub, and Vacuum is the newest category.  The end goal is to have a compilation of queries for those of us who need to keep an instance healthy.

Over the years, I have collected hundreds of various queries and hate hunting them down in my code snippet library. Finally, they will be in one place and easy to search. 

Please contribute if you have similar or better queries (hint, hint!).

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