Re: Virtual generated columns

On 09.01.25 13:41, jian he wrote:
> we can not ALTER COLUMN DROP EXPRESSION for virtual for now.
> so the following comments in generated_virtual.sql conflict with the output.
> ```
> -- check that dependencies between columns have also been removed
> ALTER TABLE gtest29 DROP COLUMN a;  -- should not drop b
> \d gtest29
> ```
> we can also comment out line 557 in generated_virtual.sql.

Ok will do.

> attach patch is removing unnecessary parentheses from
> ```ereport(ERROR, (errcode```
> only for this patch related.
> per commit https://git.postgresql.org/cgit/postgresql.git/commit/?id=e3a87b4991cc2d00b7a3082abb54c5f12baedfd1
> 
> also https://www.postgresql.org/docs/current/error-message-reporting.html says
>   ""The extra parentheses were required before PostgreSQL version 12,
> but are now optional.""

Right.  I tried to keep it mostly consistent with existing surrounding 
code, but I will do another pass to improve that.