Can we use the semantics defined by Teradata [1]? Are there any more semantics to be defined?
[1] - https://docs.teradata.com/r/e79ET77~NzPDz~Ykinj44w/MKSYuTyx2UJWXzdHJf3~sQ On Sat, Aug 20, 2022 at 11:53 AM Julian Hyde <jhyde.apa...@gmail.com> wrote: > Agreed. Aliases-in-where (enabled by a compliance flag) is a valid feature > request but you’d have to fully define the semantics. > > Julian > > > On Aug 19, 2022, at 22:46, Jiajun Xie <jiajunbernou...@gmail.com> wrote: > > > > Hi, Broeder: > > There's a tricky situation: alias may be the same as column name. Some > > users often make mistakes in company that I worked, so I have to point > out > > their problems. > > > > If you want to support alias in the WHERE clause, I hope you can consider > > how to handle this situation. > > > >> On Sat, 20 Aug 2022 at 07:31, Sean Broeder <s...@dremio.com> wrote: > >> > >> > >> > >>>> On Aug 19, 2022, at 3:57 PM, Sean Broeder <s...@dremio.com> wrote: > >>> > >>> Thanks for the clarification > >>> > >>>> On Aug 19, 2022, at 3:23 PM, Julian Hyde <jhyde.apa...@gmail.com > >> <mailto:jhyde.apa...@gmail.com>> wrote: > >>>> > >>>> Column aliases are only available in the ORDER BY clause. In some > >> dialect-compliance settings, they are also available in the GROUP BY and > >> HAVING clauses. But not in the WHERE clause. > >>> > >> Hi Julian, > >> It looks like some databases do support column aliasing in where > clauses, > >> for example, Terradata documentation indicates it does. > >> > >> > https://docs.teradata.com/r/Teradata-Database-SQL-Fundamentals/June-2017/Basic-SQL-Syntax/Referencing-Object-Names-in-a-Request/Using-a-Column-Alias > >> > >> I am interested in this feature and would contribute an enhancement to > >> Calcite if it’s possible. > >> > >> Do you happen to know if the current lack of support is due to technical > >> difficulties/limitations or it simply hasn’t been implemented yet? > >> > >> Also, if the latter, do you have a pointer to where I might start > looking? > >> > >> Thanks, > >> Sen > -- Warm Regards, Jay Narale
