Re: Re: [PATCHES] Select parser at runtime

Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:

> Ian Lance Taylor <ian(at)airs(dot)com> writes:
> > For example: the datatypes have different names; the set of reserved
> > words is different; Oracle uses a weird syntax for outer joins.
>
> Is it really possible to fix these things strictly in the parser
> (ie, without any semantic analysis)? For example, I don't quite see
> how you're going to translate Oracle-style outer joins to SQL standard
> style without figuring out which fields belong to which relations.
> Keep in mind the cardinal rule for the parsing step: Thou Shalt Not
> Do Any Database Access (because the parser must work even in
> transaction-aborted state, else how do we recognize ROLLBACK command?)

I admit that I haven't sorted out the outer join thing yet. The
others are easy enough.

Ian