On Monday, September 21, 2015, Amir Rohan <amir.ro...@mail.com> wrote:
> > From http://www.postgresql.org/docs/9.4/static/sql-select.html (and > previous version too): > ##SELECT List > <...> > Instead of an expression, * can be written in the output list as a > shorthand for all the columns of the selected rows. > Also, you can write table_name.* as a shorthand for the columns > coming from just that table. In these cases it is not > possible to specify new names with AS; the output column names will > be the same as the table columns' names. > > But, the docs elsewhere feature a query example show the use of a wildcard > for columns > as well as allowing you to assign names to as many of the leading columns > as you wish: > > WITH T0 as ( SELECT 1,2,3 ) > SELECT T0.* from T0 as T0(foo,bar) ; > > foo │ bar │ ?column? > ─────┼─────┼────────── > 1 │ 2 │ 3 > (1 row) > > The following curious variant also works: > > WITH T0 as ( SELECT 1,2,3 ) > SELECT justAnythingReally.* from T0 as justAnythingReally(foo,bar) ; > > The synoposis/grammer at the top doesn't hint at this either. I've checked > and this has been supported since at least 9.2 . > > Neither of those examples is: SELECT * AS "how would one alias this?" FROM table So what's your point? Obviously you can alias stuff before it makes its way into a select-list that refers to it using * In this case the FROM clause is what is being alised. It is documented though I'd need to look to identify the specific location. It would not be documented in a section regarding the select-list. David J.
