RE: DELETE/DROP on Columns

> -----Original Message-----
> From: Hiroshi Inoue
> 
> > -----Original Message-----
> > From: Thomas Swan
> >     
> > I know as far as 7.0.x and back you cannot delete/drop columns from a 
> > table.   Is this expected to be in the 7.x series?
> >
> 
> Recently there has been a discussion about this issue.
> Tom proposed a soltution which uses 2(logical/physical)
> attribute numbers. It seems the most reasonable solution
> at present.
> If there's no objection,I would try to implement it according
> to his proposal before 7.1.  
>

Oops,there remains some problems however.
They seems to be pretty serious.

1)  Which(logical or physical) attribute number should other    system tables have ?    e.g.
pg_index,pg_relcheck,pg_attrdefetc ...    For backend modules,physical attrbiute number is sufficeint    but client
programswhich handle metadata would need     logical attribute numbers. 
 

2) How do we handle logical/physical tuple format ?   For example,there's a function in test/tegress/sql/
create_function_2.sqlwhich takes a table type input   parameter and returns setof a table type.
 
   CREATE FUNCTION equipment(hobbies_r)       RETURNS setof equipment_r       AS 'select * from equipment_r where hobby
=$1.name'       LANGUAGE 'sql';
 
   This function returns equipment_r tuples of logical format   which may be different from the physical format which
isused to store heap tuples once a column is dropped.   Should input hobbies_r be of logical format also ?
 

Any comments & suggestions would be appreciated...
Regards.

Hiroshi Inoue
Inoue@tpf.co.jp