Thread: Adding // comments (ANSI??)...
I just had a friend over at EDS ask me if PostgreSQL supported // comments. It didn't, so I put together a patch for them so that they could retain compatiblity across the databases they work on. I didn't think much of it until I took a gander at the crash-me page on mysql.com and I couldn't find a single vendor that supports // comments, but it did list // as an ANSI supported comment. ::shrug:: I don't have a copy of the spec, so someone more knowledgable in that area will have to speak to this or whether or not support for // is even wantd, but, here's the patch and regression tests. -sc -- Sean Chittenden
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As far as I'm aware, MySQL is the only database that supports '//' as a comment, and they made it up out of whole cloth... ANSI _C_ perhaps... Chris > -----Original Message----- > From: pgsql-patches-owner@postgresql.org > [mailto:pgsql-patches-owner@postgresql.org]On Behalf Of Sean Chittenden > Sent: Wednesday, 5 February 2003 7:22 AM > To: pgsql-patches@postgresql.org > Subject: [PATCHES] Adding // comments (ANSI??)... > > > I just had a friend over at EDS ask me if PostgreSQL supported // > comments. It didn't, so I put together a patch for them so that they > could retain compatiblity across the databases they work on. > > I didn't think much of it until I took a gander at the crash-me page > on mysql.com and I couldn't find a single vendor that supports // > comments, but it did list // as an ANSI supported comment. ::shrug:: > I don't have a copy of the spec, so someone more knowledgable in that > area will have to speak to this or whether or not support for // is > even wantd, but, here's the patch and regression tests. -sc > > -- > Sean Chittenden >
> > I just had a friend over at EDS ask me if PostgreSQL supported // > > comments. It didn't, so I put together a patch for them so that they > > could retain compatiblity across the databases they work on. > > > > I didn't think much of it until I took a gander at the crash-me page > > on mysql.com and I couldn't find a single vendor that supports // > > comments, but it did list // as an ANSI supported comment. ::shrug:: > > I don't have a copy of the spec, so someone more knowledgable in that > > area will have to speak to this or whether or not support for // is > > even wantd, but, here's the patch and regression tests. -sc > > As far as I'm aware, MySQL is the only database that supports '//' > as a comment, and they made it up out of whole cloth... > > ANSI _C_ perhaps... MySQL doesn't support //, unless you meant #. http://www.mysql.com/information/crash-me.php http://www.mysql.com/doc/en/Comments.html http://www.mysql.com/doc/en/ANSI_diff_comments.html Hrm, well, sybase, Microsoft, and a thing called "AceDB" do, but I haven't seen high nor low of // being actually referenced as an ANSI sanctioned comment style anywhere. I guess that's just for the archives or the C++/Java impared. ::shrug:: http://manuals.sybase.com/onlinebooks/group-aw/awg0800e/dbrfen8/@Generic__BookTextView/7074 http://www.microsoft.com/mspress/books/sampchap/4076a.asp http://www.acedb.org/Cornell/syntax.html -sc -- Sean Chittenden
On Tue, 2003-02-04 at 21:03, Christopher Kings-Lynne wrote:
> As far as I'm aware, MySQL is the only database that supports '//' as a
> comment, and they made it up out of whole cloth...
Just to confirm that, my copy of the SQL 2003 draft, section 5.2, says:
<comment> ::=
<simple comment>
| <bracketed comment>
<simple comment> ::=
<simple comment introducer> [ <comment characters>...] <newline>
<simple comment introducer> ::=
<minus sign><minus sign>[<minus sign>...]
(and <bracketed comment> is a C-style /* ... */ pair, which I've omitted
for brevity).
I'm not sure where the evidence for the "ANSI standard" claim comes
from, but AFAICS "// comments" are not part of the SQL standard, at any
rate.
Cheers,
Neil
--
Neil Conway <neilc@samurai.com> || PGP Key ID: DB3C29FC
Sean Chittenden <sean@chittenden.org> writes:
> I didn't think much of it until I took a gander at the crash-me page
> on mysql.com and I couldn't find a single vendor that supports //
> comments, but it did list // as an ANSI supported comment. ::shrug::
MySQL seem to have only a very weak grasp on the notion of "spec
compliance" ;-). // is most definitely not a comment in the SQL spec.
Furthermore, it's a legal operator name in Postgres.
regards, tom lane
> > I didn't think much of it until I took a gander at the crash-me > > page on mysql.com and I couldn't find a single vendor that > > supports // comments, but it did list // as an ANSI supported > > comment. ::shrug:: > > MySQL seem to have only a very weak grasp on the notion of "spec > compliance" ;-). // is most definitely not a comment in the SQL > spec. At best a weak notion of spec compliance. You should read about the use of '--' as a comment and why '--' has to have a space after it in order for it to be a valid comment: I found it highly amusing. :) Anyway, Neil, thanks for looking that up: I don't have a copy of the standard and thought it was a tad strange to see it listed as an ANSI comment (assuming they meant ANSI SQL and not ANSI C99), especially since I couldn't find _any_ references suggesting // as a valid SQL token. :) -sc -- Sean Chittenden