Re: [HACKERS] SAVEPOINT syntax again

Making the assumption that we want standards-conforming syntax here, I
went ahead and did the necessary changes:

Oliver Jowett wrote:

> Comments:
>
> 1) We have a different syntax to the SQL200n draft (and Oracle by the
> looks of it) for ROLLBACK. The draft says:
>
>> <rollback statement> ::= ROLLBACK [ WORK ] [ AND [ NO ] CHAIN ] [
>> <savepoint clause> ]
>> <savepoint clause> ::= TO SAVEPOINT <savepoint specifier>

Oracle has ROLLBACK TO [ SAVEPOINT ] <savepoint specifier>
DB2 has ROLLBACK TO SAVEPOINT <savepoint specifier>

> 2) We have a different syntax for RELEASE too. The SQL200n draft says:
>
>> <release savepoint statement> ::= RELEASE SAVEPOINT <savepoint specifier>

Oracle does not have RELEASE SAVEPOINT.
DB2 has RELEASE [ TO ] SAVEPOINT <savepoint specifier>

The attached patch implements an approximate union of the above syntaxes:

ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] <savepoint specifier>
RELEASE [ TO ] SAVEPOINT <savepoint specifier>

Note that this means that "RELEASE foo" is no longer valid. It seems
solely a postgresql-ism -- anyone particularly attached to that syntax?

Also in the patch are documentation and regression test updates to
reflect the new syntax. I have changed the examples in the docs and the
regression tests to prefer the standard-conforming variants. Error
messages now refer to ROLLBACK TO SAVEPOINT and RELEASE SAVEPOINT rather
than ROLLBACK TO and RELEASE.

-O