Yes, there are more semantics to be defined. Think of the tricky edge cases, try them on Teradata and any other databases with these semantics, design error messages, and write tests.
> On Aug 22, 2022, at 1:37 PM, Jay Narale <jaynarale3...@gmail.com> wrote: > > 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
