Show the structure of the query

[Krysztophe]

NB : Linked to #294 and perhaps #485

When reading a query, it is sometimes difficult to know immediately which tables are linked to which ones,
on which keys, and where are the filters,
especially when the query puts the joins as WHERE clauses and not ON clauses.

Very often, I take a pen and draw the structure.

I don't know of an existing tool that does it from the query.

The result would be like the "structure" from explain-postgresql.com.

Maybe does a SQL parser that ouputs a graphical query already exists, bu I didn't find it.

Perhaps a view like #294 (structure from the plan) would be a first step.