Support JOIN TO ONE syntax

[EPluribusUnum]

Hi *!

Syntactic sugar and safeguard for joins
https://blogs.oracle.com/sql/avoid-join-duplicates-with-modern-join-syntax-in-oracle-ai-database

[sim1984]

I don't think we should implement syntactic sugar that isn't accepted in the SQL standard. Perhaps it will be included in the standard in the future, and then we can consider it. And it's not a given that adding such a feature to the standard will preserve Oracle's syntax.

For example, recursive queries have existed in Oracle for a long time, but they were added to the SQL standard later, and their syntax is different.