Is this an analysis time thing or a runtime thing? On Tue, Dec 18, 2018 at 7:45 AM Marco Gaido <marcogaid...@gmail.com> wrote:
> Hi all, > > as you may remember, there was a design doc to support operations > involving decimals with negative scales. After the discussion in the design > doc, now the related PR is blocked because for 3.0 we have another option > which we can explore, ie. forbidding negative scales. This is probably a > cleaner solution, as most likely we didn't want negative scales, but it is > a breaking change: so we wanted to check the opinion of the community. > > Getting to the topic, here there are the 2 options: > * - Forbidding negative scales* > Pros: many sources do not support negative scales (so they can create > issues); they were something which was not considered as possible in the > initial implementation, so we get to a more stable situation. > Cons: some operations which were supported earlier, won't be working > anymore. Eg. since our max precision is 38, if the scale cannot be negative > 1e36 * 1e36 would cause an overflow, while now works fine (producing a > decimal with negative scale); basically impossible to create a config which > controls the behavior. > > *- Handling negative scales in operations* > Pros: no regressions; we support all the operations we supported on 2.x. > Cons: negative scales can cause issues in other moments, eg. when saving > to a data source which doesn't support them. > > Looking forward to hear your thoughts, > Thanks. > Marco > > >
