Wood May <asdf_pg@outlook.com> writes:
>     Some databases (like Teradata) support the following syntax:
>     select col1, col2*20 as col2_1, col2_1*200 as col3_1 from your_table;
>     The last element in the target list can refer the second one using its alias.
>     This feature is similar to some programming languages (like Lisp)'s let*.
>     For Postgres, it seems the only way is to write a subquery and then a new target list.
>     Will Postgres plan to support this feature?
No.  It's flat out contrary to the SQL standard.
            regards, tom lane