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Create multiple sqlite tables, many-to-many design


On Thu, Aug 15, 2019 at 7:41 PM Gregory Ewing
<greg.ewing at canterbury.ac.nz> wrote:
>
> Chris Angelico wrote:
> > I prefer to say "Trails" for the table, and "Trail" would then refer
> > to a single row from that table.
>
> That makes sense for a data structure in your program that contains a
> collection of rows. But I've come to the view that SQL tends to read
> better if the names of the database tables are singular, because in SQL
> you're writing assertions about individual rows, not the tables in
> their entirety.
>
> So I would write something like
>
>     select T.name, T.id from Trail T
>
> but I would assign the resulting list of rows to a variable named
> "trails" in my program.
>

You're selecting from a collection of trails. I don't see a conflict
here. It's the same as taking a list of values and then filtering it -
even though assertions are made about individuals, you are filtering
the entire list:

early_things = [thing for thing in things if thing.name < 'M']

ChrisA