Thread: add operator ^= to mean not equal (like != and <>)
Hi everyone,
I am doding some jobs in postgres. I want to add "^=" like "!=" and "<>".
So i modify the code in scan.l.
Plan 1:
equals_greater "=>"
less_equals "<="
greater_equals ">="
less_greater "<>"
not_equals (!=|\^=)
Maybe i can delete some code to make the code more simple.
Plan 2:
equals_greater "=>"
less_equals "<="
greater_equals ">="
less_greater "<>" (delete this definition)
not_equals (!=|\^=|<>)
Before send patch review, I want to konw whether the postgres maintainer will approve my changes.
So, please give me some advice.
Thank you!
On 8/10/21 10:27 AM, 孙诗浩(思才) wrote: > Before send patch review, I want to konw whether the postgres maintainer > will approve my changes. > > So, please give me some advice. Welcome! I do not think that is a feature which will get much interest from the developers since it is unclear to me what the advantage of yet another alias for not equal would be. It just takes up yet another operator and means that there is yet another thing to remember for the users. Personally I feel it is bad enough that we have two ways of writing it. What is he reason you want to add ^= is there any other databases which uses ^= for inequality? Andreas
> On 10 Aug 2021, at 11:10, Andreas Karlsson <andreas@proxel.se> wrote: > What is he reason you want to add ^= is there any other databases which uses ^= for inequality? I assume it's because of Oracle compatibility which AFAIK is the only database supporting ^=. -- Daniel Gustafsson https://vmware.com/
On Tue, 10 Aug 2021 at 21:13, Daniel Gustafsson <daniel@yesql.se> wrote: > > > On 10 Aug 2021, at 11:10, Andreas Karlsson <andreas@proxel.se> wrote: > > > What is he reason you want to add ^= is there any other databases which uses ^= for inequality? > > I assume it's because of Oracle compatibility which AFAIK is the only database > supporting ^=. Seems likely. I'm strongly against inheriting warts from Oracle for apparently good reason. At the very least, anyone who's using ^= for some other purpose is very likely to be upset with us. Anyone else who really needs this for compatibility reasons can just create a set of operators for themselves. David
> On 10 Aug 2021, at 12:21, David Rowley <dgrowleyml@gmail.com> wrote: > > On Tue, 10 Aug 2021 at 21:13, Daniel Gustafsson <daniel@yesql.se> wrote: >> >>> On 10 Aug 2021, at 11:10, Andreas Karlsson <andreas@proxel.se> wrote: >> >>> What is he reason you want to add ^= is there any other databases which uses ^= for inequality? >> >> I assume it's because of Oracle compatibility which AFAIK is the only database >> supporting ^=. > > Seems likely. > > I'm strongly against inheriting warts from Oracle for apparently good > reason. At the very least, anyone who's using ^= for some other > purpose is very likely to be upset with us. Anyone else who really > needs this for compatibility reasons can just create a set of > operators for themselves. Agreed, if it’s because of Oracle compatibility then this seems like something which has a better fit in orafce or a similar extension like that. -- Daniel Gustafsson https://vmware.com/
Le mar. 10 août 2021 à 18:41, Daniel Gustafsson <daniel@yesql.se> a écrit :
> On 10 Aug 2021, at 12:21, David Rowley <dgrowleyml@gmail.com> wrote:
>
> I'm strongly against inheriting warts from Oracle for apparently good
> reason. At the very least, anyone who's using ^= for some other
> purpose is very likely to be upset with us. Anyone else who really
> needs this for compatibility reasons can just create a set of
> operators for themselves.
Agreed, if it’s because of Oracle compatibility then this seems like something
which has a better fit in orafce or a similar extension like that.
+1
On 10/08/21 8:27 pm, 孙诗浩(思才) wrote:
> Hi everyone,
> I am doding some jobs in postgres. I want to add "^=" like "!=" and "<>".
One problem is that '^' & '^=' is already used as the exclusive OR
operator in programming languages such as: C, Java, JavaScript, and
Python. See:
https://www.tutorialspoint.com/java/java_basic_operators.htm
https://www.tutorialspoint.com/cprogramming/c_operators.htm
https://docs.python.org/3/library/operator.html
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Expressions_and_Operators
Please don't confuse people unnecessarily!
Cheers,
Gavin
Hi, On Tue, Aug 10, 2021 at 11:13:03AM +0200, Daniel Gustafsson wrote: > > On 10 Aug 2021, at 11:10, Andreas Karlsson <andreas@proxel.se> wrote: > > What is he reason you want to add ^= is there any other databases > > which uses ^= for inequality? > > I assume it's because of Oracle compatibility which AFAIK is the only > database supporting ^=. DB2 also supports (or supported) it, but it's deprecated: https://www.ibm.com/docs/en/db2/9.7?topic=predicates-basic-predicate We encountered it at least in one customer setting, so we added it to db2fce: https://github.com/credativ/db2fce/blob/master/db2fce.sql#L588 Michael -- Michael Banck Projektleiter / Senior Berater Tel.: +49 2166 9901-171 Fax: +49 2166 9901-100 Email: michael.banck@credativ.de credativ GmbH, HRB Mönchengladbach 12080 USt-ID-Nummer: DE204566209 Trompeterallee 108, 41189 Mönchengladbach Geschäftsführung: Dr. Michael Meskes, Sascha Heuer, Geoff Richardson, Peter Lilley Unser Umgang mit personenbezogenen Daten unterliegt folgenden Bestimmungen: https://www.credativ.de/datenschutz