Gavin 'Beau' Baumanis wrote:
>
> The copy is inside the same table, so I don't understand why it (the
> required query ) would require any joins.
>
> Ie. I want to copy the contents of a row (but for the id column - of
> course) into a record in the same table.
I think what you want is something like this:
Given (col1 being the id or PK):
col1 | col2 | col3
------+------+--------------- 1 | 123 | first record 2 | 456 | second record 3 | 789 | third record
then
update t1 set col2 = t1copy.col2, col3 = t1copy.col3
from t1 as t1copy
where t1.col1 = 1 and t1copy.col1 = 3;
will result in:
col1 | col2 | col3
------+------+--------------- 1 | 789 | third record 2 | 456 | second record 3 | 789 | third record
So, it is a join ... of a table with a virtual copy of itself.
Joe