Обсуждение: AW: New warning code for missing FROM relations
> > > SELECT * > > > INTO TABLE tmp1 > > > FROM tmp > > > WHERE onek.unique1 < 2; > > > NOTICE: Adding missing FROM-clause entry for table onek > > > Is is worth adding yet another setting, eg. set sql92=strict, which > > would disallow such flagrant breaches of the standard? > > SQL provides for facility called the SQL Flagger, which is > supposed to do > exactly that. This might sound like an interesting idea but > in order for > it to be useful you'd have to maintain it across the board, > which sounds > like a major head ache. > > The irony in the given example is that the SELECT INTO > command isn't in > the standard in the first place so you'd have to create all sorts of > double standards. Certain things would be "extensions", certain things > would be "misuse". And for all it's worth, we have no idea > which is which. > > If you want to throw about warnings about "probable" coding > errors and the > like one *must* be able to switch them off. Either something is right, > then you shut up. Or it's wrong, then you throw an error. Or > you're not > sure, then you better leave it up to the user. Yes, only Bruce and I are of the opinion that it *is* an Error, and I guess we want some consensus. The notice is imho of the sort: notice this syntax is going to be disallowed soon. Andreas
> > The irony in the given example is that the SELECT INTO > > command isn't in > > the standard in the first place so you'd have to create all sorts of > > double standards. Certain things would be "extensions", certain things > > would be "misuse". And for all it's worth, we have no idea > > which is which. > > > > If you want to throw about warnings about "probable" coding > > errors and the > > like one *must* be able to switch them off. Either something is right, > > then you shut up. Or it's wrong, then you throw an error. Or > > you're not > > sure, then you better leave it up to the user. > > Yes, only Bruce and I are of the opinion that it *is* an Error, and I guess > we want some consensus. > The notice is imho of the sort: notice this syntax is going to be disallowed > soon. I see the notice as "Hey, you probably did something you didn't want to do". -- Bruce Momjian | http://www.op.net/~candle pgman@candle.pha.pa.us | (610) 853-3000+ If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania19026
At 10:02 5/06/00 +0200, Zeugswetter Andreas SB wrote: > >> > > SELECT * >> > > INTO TABLE tmp1 >> > > FROM tmp >> > > WHERE onek.unique1 < 2; >> > > NOTICE: Adding missing FROM-clause entry for table onek >> > >Yes, only Bruce and I are of the opinion that it *is* an Error, and I guess >we want some consensus. >The notice is imho of the sort: notice this syntax is going to be disallowed >soon. > FWIW, I think it's an error too. For me, this situation is *far* more likely to result from typos than intention, and I want to be told when it happens. I also want to be prevented from doing it. I take it that there is no chance of a compile-time or runtime option to disallow this kind of thing in all cases? ---------------------------------------------------------------- Philip Warner | __---_____ Albatross Consulting Pty. Ltd. |----/ - \ (A.C.N. 008 659 498) | /(@) ______---_ Tel: +61-03-5367 7422 | _________ \ Fax: +61-03-5367 7430 | ___________ | Http://www.rhyme.com.au | / \| | --________-- PGP key available upon request, | / and from pgp5.ai.mit.edu:11371 |/
Philip Warner <pjw@rhyme.com.au> writes:
> I take it that there is no chance of a compile-time or runtime option to
> disallow this kind of thing in all cases?
Define "all cases" ... also, just how strict do you want to be?
Disallow use of *any* Postgres feature that is not in SQL92 (that
would include all user datatypes and functions, for example)?
Postgres was never designed as an SQL compatibility checker, and
I doubt that it'd be cost-effective to try to turn it into one.
A standalone tool might be a better approach.
Perhaps there is someone out there who wants this feature badly
enough to do the legwork, but I'm not him ;-)
regards, tom lane
> Philip Warner <pjw@rhyme.com.au> writes: > > I take it that there is no chance of a compile-time or runtime option to > > disallow this kind of thing in all cases? > > Define "all cases" ... also, just how strict do you want to be? > Disallow use of *any* Postgres feature that is not in SQL92 (that > would include all user datatypes and functions, for example)? > > Postgres was never designed as an SQL compatibility checker, and > I doubt that it'd be cost-effective to try to turn it into one. > A standalone tool might be a better approach. > > Perhaps there is someone out there who wants this feature badly > enough to do the legwork, but I'm not him ;-) Agreed. Seems the current warning level as configured is in the middle of people's expections on this issue. -- Bruce Momjian | http://www.op.net/~candle pgman@candle.pha.pa.us | (610) 853-3000+ If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania19026
At 11:44 5/06/00 -0400, Tom Lane wrote: >Philip Warner <pjw@rhyme.com.au> writes: >> I take it that there is no chance of a compile-time or runtime option to >> disallow this kind of thing in all cases? > >Define "all cases" ... also, just how strict do you want to be? >Disallow use of *any* Postgres feature that is not in SQL92 (that >would include all user datatypes and functions, for example)? Sorry, I should have been a bit more specific! I would like some kind of option to disable all cases of adding tables to FROM clauses by implication. The main issue I have with this feature is it is more likely to be used (by me) by accident (as a result of a typo), and consequently introduce very strange results. I am unaware (yet? ;-}) of any other non-SQL features in PostgreSQL that are likely to cause me the same level of concern. Adding tables to a query seems very dangerous: some people might, for example, expect an automatic natural join on primary/foreign keys if you add a table. ---------------------------------------------------------------- Philip Warner | __---_____ Albatross Consulting Pty. Ltd. |----/ - \ (A.C.N. 008 659 498) | /(@) ______---_ Tel: +61-500 83 82 81 | _________ \ Fax: +61-500 83 82 82 | ___________ | Http://www.rhyme.com.au | / \| | --________-- PGP key available upon request, | / and from pgp5.ai.mit.edu:11371 |/
Bruce Momjian writes: > I see the notice as "Hey, you probably did something you didn't want > to do". Again, "probably" means you're not sure, so you leave it up to the user to turn it on or off. -- Peter Eisentraut Sernanders väg 10:115 peter_e@gmx.net 75262 Uppsala http://yi.org/peter-e/ Sweden
Zeugswetter Andreas SB writes: > Yes, only Bruce and I are of the opinion that it *is* an Error, and I > guess we want some consensus. I agree that it is an error. > The notice is imho of the sort: notice this syntax is going to be > disallowed soon. If you can guarantee that each user will only see the notice once, then okay. :) -- Peter Eisentraut Sernanders väg 10:115 peter_e@gmx.net 75262 Uppsala http://yi.org/peter-e/ Sweden
[ Charset ISO-8859-1 unsupported, converting... ] > Zeugswetter Andreas SB writes: > > > Yes, only Bruce and I are of the opinion that it *is* an Error, and I > > guess we want some consensus. > > I agree that it is an error. > > > The notice is imho of the sort: notice this syntax is going to be > > disallowed soon. > > If you can guarantee that each user will only see the notice once, then > okay. :) There is no sense that this is a warning about the syntax changing at some point. It is to warn queries that are probably broken. Seems if they already have a FROM clause, there is no purpose for some tables being in the FROM clause, and others begin auto-created. In other cases, it issues no warning. -- Bruce Momjian | http://www.op.net/~candle pgman@candle.pha.pa.us | (610) 853-3000+ If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania19026