ne 10. 11. 2024 v 18:51 odesílatel Pavel Stehule <pavel.steh...@gmail.com> napsal:
> > > ne 10. 11. 2024 v 17:19 odesílatel Pavel Stehule <pavel.steh...@gmail.com> > napsal: > >> >> >> ne 10. 11. 2024 v 16:24 odesílatel Dmitry Dolgov <9erthali...@gmail.com> >> napsal: >> >>> Hi folks, >>> >>> Thanks for continuing this work. As a side note, I would like to mention >>> how strange the situation in this CF item is. If I understand correctly, >>> there are two hackers threads discussing the same patch, with recent >>> patches posted in both of them. This is obviously confusing, e.g. the >>> main concern from another thread, about names clashing, wasn't even >>> mentioned in this one. Is it possible to reconcile development in one >>> thread? >>> >> >> This is probably my error. I don't try to organize threads, just I'll try >> to reply in the thread where I got a question. >> > > I thought a lot of time about better solutions for identifier collisions > and I really don't think so there is some consistent user friendly syntax. > Personally I think there is an easy already implemented solution - > convention - just use a dedicated schema for variables and this schema > should not be in the search path. Or use secondary convention - like using > prefix "__" for session variables. Common convention is using "_" for > PLpgSQL variables. I searched how this issue is solved in other databases, > or in standard, and I found nothing special. The Oracle and SQL/PSM has a > concept of visibility - the variables are not visible outside packages or > modules, but Postgres has nothing similar. It can be emulated by a > dedicated schema without inserting a search path, but it is less strong. > There can be more collisions in Oracle, because the functions without arguments don't need parentheses. Postgres is safer, because this syntax is not allowed. > > I think we can introduce an alternative syntax, that will not be user > friendly or readable friendly, but it can be without collisions - or can > decrease possible risks. > > It is nothing new - SQL does it with old, "new" syntax of inner joins, or > in Postgres we can > > where salary < 40000 > > or > > where pg_catalog.int4lt(salary, 40000); > > > or some like we use for operators OPERATOR(*schema*.*operatorname*) > > So introducing VARIABLE(schema.variablename) syntax as an alternative > syntax for accessing variables I really like. I strongly prefer to use this > as only alternative (secondary) syntax, because I don't think it is > friendly syntax or writing friendly, but it is safe, and I can imagine > tools that can replace generic syntax to this special, or that detects > generic syntax and shows some warning. Then users can choose what they > prefer. Two syntaxes - generic and special can be good enough for all - and > this can be perfectly consistent with current Postgres. > > Regards > > Pavel > > >> Regards >> >> Pavel >> >> >
