[kevincox]

I think left join is a bad name. Probably something like OPTIONAL JOIN or TRY JOIN would be more obvious. Of course the problem is then what do you call a right join? REVERSE OPTIONAL JOIN? But that is getting pretty confusing now. But maybe worth it because in my experience left is far more common.

[samatman]

It's best to pretend that RIGHT JOIN doesn't exist, imnsho.

For one thing, in SQLite, it doesn't. Which is a weak argument for not using it on supported systems. The other weak argument is that a RIGHT JOIN is just the b, a version of a LEFT JOIN a, b.

When you add them up it's an extra concept, SQL execution flow is already somewhat unintuitive, and a policy of using one of the two ways of saying "everything from a and matches from b" makes for a more consistent codebase.

I would hope a blue-sky relational query language wouldn't support two syntaxes for an operation which is non-commutative, when order is important it can and should be indicted by order.

[debugnik]

> For one thing, in SQLite, it doesn't.

It does now, since the latest release 3.39, along with full join.

[samatman]

That's great news!

It'll be a long time before one can use it in portable SQLite queries, for those cases where that matters. I'll continue to eschew the right join for the clarity of only thinking about that relation in one way, but we statically link SQLite for several good reasons, including being able to use new features as they arrive.

Full join is certainly a welcome addition.

[motoboi]

It's actually pretty obvious name. You just need to visualize a Venn diagram and left, right and inner become obvious.