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

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