In general, I don't like those X-to-Y translation pages, when the underlying concepts fundamentally change. You can't use your existing sql mindset to translate to their query language, but instead try to learn from scratch.
I don't know. I think they're useful if you consider them as a "I want to do X in languages A and B" showcase rather than a literal translation guide. It can certainly help getting a feel for "how much more difficult/easier is this in A vs B?".
We have a similar page at ArangoDB to help developers used to SQL to understand the general differences in AQL: https://www.arangodb.com/why-arangodb/sql-aql-comparison/