James, thanks for the reminder on EXTENDS. And Julian, thanks for the reminder of the _MAP, that must have been what I was remembering. I'm actually looking for something slightly different:
I want a column to exists for validation when explicitly requested but be excluded from star expansion. Any other ideas on how to handle this? Think ROWNUM in Oracle. I guess they call it a pseudocolumn. On Mon, Apr 17, 2017 at 11:49 PM, Julian Hyde <[email protected]> wrote: > There’s also the “_MAP” column returned by the MongoDB and Elasticsearch > adapters. It contains a (key, value) pair for the top-level fields of each > row. It DOES appear in SELECT *. > > We had the idea of rewriting > > SELECT empno FROM Emp > > to > > SELECT _MAP[‘empno’] FROM Emp > > if Emp had a particular row type but I don’t think we ever did it. > > Julian > > > > > > On Apr 17, 2017, at 7:27 PM, James Taylor <[email protected]> > wrote: > > > > Hey Jacques, > > The EXTENDS (col1 type, col2 type) keyword can be used for this (and the > > EXTENDS keyword is optional). Something like this in Phoenix: > > > > SELECT foo FROM bar (my_col VARCHAR) WHERE my_col = 'bas' > > > > Phoenix uses this for dynamic column support. > > > > Thanks, > > James > > > > On Mon, Apr 17, 2017 at 7:17 PM, Jacques Nadeau <[email protected]> > wrote: > > > >> Hey All, > >> > >> I remember there being a syntax in Calcite that allowed one to define an > >> _EXTRA column or columns that could be referenced in Calcite but > wouldn't > >> be included in a select *. If I recall, the Splunk adapter used this at > one > >> point. Does this actually exist or have I lost my mind. I can't seem to > >> find a reference to this anywhere. > >> > >> thanks! > >> > >
