Re: SET TRANSACTION and SQL Standard

Heikki Linnakangas wrote:
> Simon Riggs wrote:
> > On Fri, 2009-01-09 at 16:14 +0200, Peter Eisentraut wrote:
> >> Simon Riggs wrote:
> >>> I notice that we allow commands such as
> >>>
> >>> SET TRANSACTION read only read write read only;
> >>>
> >>> BEGIN TRANSACTION read only read only read only;
> >>>
> >>> Unsurprisingly, these violate the SQL Standard:
> >>> * p.977 section 19.1 syntax (1)
> >>> * p.957 section 17.3 syntax (2)
> >> Well, we allow a lot of things. Violations of the SQL standard happen
> >> when a command that appears in the standard doesn't do what the standard
> >> says. Allowing commands that are not in the standard is not a violation.
> >
> > Except when the standard explicitly forbids it, as with the above.
>
> No, it just means that the statement "SET TRANSACTION read only read
> write read only;" doesn't conform to the standard, and it's therefore
> implementation-dependent what it does. See the meaning of "shall" in
> Syntax Rules, section "6.3.3.2 Terms denoting rule requirements".
>
> I agree with Tom that the 2nd form is harmless, but we should throw an
> error for the first.

Added to TODO:

Prevent the specification of conflicting transaction read/write
options

* http://archives.postgresql.org/pgsql-hackers/2009-01/msg00684.php

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Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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