Thomas Kellerer <spam_ea...@gmx.net> writes:
> I don't understand why going from numeric(12,2) to numeric(15,3) would
> require a table rewrite.
The comment for numeric_transform explains this:
* Flatten calls to numeric's length coercion function that solely represent
* increases in allowable precision. Scale changes mutate every datum, so
* they are unoptimizable. Some values, e.g. 1E-1001, can only fit into an
* unconstrained numeric, so a change from an unconstrained numeric to any
* constrained numeric is also unoptimizable.
The issue is basically that changing '1.00' to '1.000' requires a change
in the actually-stored value.
regards, tom lane
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
