remove documented limitation that no longer applies

[petrosagg]

...and a syntax fix

Motivation

Tips for reviewer

Checklist

• This PR has adequate test coverage / QA involvement has been duly considered. (trigger-ci for additional test/nightly runs)
• This PR has an associated up-to-date design doc, is a design doc (template), or is sufficiently small to not require a design.
• If this PR evolves an existing $T ⇔ Proto$T mapping (possibly in a backwards-incompatible way), then it is tagged with a T-proto label.
• If this PR will require changes to cloud orchestration or tests, there is a companion cloud PR to account for those changes that is tagged with the release-blocker label (example).
• If this PR includes major user-facing behavior changes, I have pinged the relevant PM to schedule a changelog post.

[kay-kim]

So ... MySQL and SQL Server .... they are the old syntax for now, yes? Or is it that these statements were obsolete, even with the old syntax.

[petrosagg]

Exactly, they are obsolete in general

[martykulma]

Thanks @petrosagg!

@petrosagg pointed out that the partition by syntax is valid, but there really isn't any user visible impact to setting it. This PR removes mention from the SQL example, but in the rendered page, PARTITION BY is still listed under WITH <with_options>, it just doesn't have any description because this syntax doesn't do anything.

My vote would be to remove the the syntax from the docs if it doesn't do anything, but leaving it in doesn't hurt anything.

[kay-kim]

Agree w. removing from options as well. I'll just merge this and update to minimize the moving parts.