On Sun, Oct 1, 2023 at 05:30:39AM -0400, Ann Harrison wrote:
> Other databases do allow that sort of gradual migration. One example
> has an internal table of record descriptions indexed the table identifier
> and a description number. Each record includes a header with various
> useful bits including its description number. When reading a record,
> the system notes the description number and looks up the description
> before parsing the record into columns.
>
> The transition is made easier if the database indexes are generic -
> for example, numbers rather than decimal[12,6], int32, etc., and string
> rather than varchar[12]. That way, increasing a column size doesn't
> require re-indexing.
>
> But, those are decision that really had to be made early - making
> a major format change 25+ years in would break too much.
And the performance sounds terrible. ;-)
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EDB https://enterprisedb.com
Only you can decide what is important to you.