I think we need to do this for backward compatibility, and according to the discussion in the doc, SQL standard allows negative scale.
To do this, I think the PR should also include a doc for the decimal type, like the definition of precision and scale(this one <https://stackoverflow.com/questions/35435691/bigdecimal-precision-and-scale> looks pretty good), and the result type of decimal operations, and the behavior when writing out decimals(e.g. we can cast decimal(1, -20) to decimal(20, 0) before writing). Another question is, shall we set a min scale? e.g. shall we allow decimal(1, -10000000)? On Thu, Oct 25, 2018 at 9:49 PM Marco Gaido <marcogaid...@gmail.com> wrote: > Hi all, > > a bit more than one month ago, I sent a proposal for handling properly > decimals with negative scales in our operations. This is a long standing > problem in our codebase as we derived our rules from Hive and SQLServer > where negative scales are forbidden, while in Spark they are not. > > The discussion has been stale for a while now. No more comments on the > design doc: > https://docs.google.com/document/d/17ScbMXJ83bO9lx8hB_jeJCSryhT9O_HDEcixDq0qmPk/edit#heading=h.x7062zmkubwm > . > > So I am writing this e-mail in order to check whether there are more > comments on it or we can go ahead with the PR. > > Thanks, > Marco >
