AR has a to_sql method, as long as You are fine with AR, You can generate SQL.
My favorite DB author to learn SQL, Joe Celko 
kokolegorille
peerreynders
kokolegorille
peerreynders
Sure - however AR isn’t available in Ecto (or Phoenix) and I don’t know how much effort it would be to set up a piggybacked environment just for the purpose of generating SQL from active record.
Joe Celko’s stuff is interesting but from what I remember some of the content dealt with a “(prerelease-)reference-level ANSI SQL” that may or may not work on most platforms in the manner presented (so sometimes “translation” may be required). While SQL isn’t exactly moving at the same pace as JavaScript, a lot of his content has been around for awhile, the last (advanced) book update being from 2014.
For the purposes of getting the most out of Programming Ecto
is probably the best bet. The bits of the tutorial I have come across seem to do the job.
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