Personally I would prefer to display the expression as what users write. But I agree with Haisheng.
Maybe we can add an optimizer config option to enable/disable this feature. Best, Chunwei On Tue, Dec 31, 2019 at 9:50 AM Haisheng Yuan <[email protected]> wrote: > Normalizing scalar expressions is helpful, especially for deduplicating > derived constraints that is pushed down to child relations. We should not > stop making improvements just because there are many plan changes. > > How about adding optimizer config option to enable/disable the feature? > > Normalizing every binary operator might seem not necessary, but simply > normalizing equal expression with input refs or literals alone can still > help a lot, I guess, because many of them are generated from equivalent > classes. > > - Haisheng > > ------------------------------------------------------------------ > 发件人：Rui Wang<[email protected]> > 日 期：2019年12月31日 07:09:44 > 收件人：<[email protected]> > 主 题：Re: [DISCUSS] CALCITE-2450 reorder predicates to a canonical form > > I think the concern of breaking plan comparison has appeared more than > once. Not only to this proposal but also to others (e.g. replace "$" with > "_" in names). > > From a think of another perspective, the widely used practice of > string comparison based plan evaluation also reduces the flexibility of > making changes in Calcite. We need to carefully think about if a change has > a large impact that affects toString(), or something similar. > > So if Calcite community could offer another solution for downstream > projects, and announce that don't guarantee the backward compatibility of > toString(), then it could be in a better situation. > > A few candidate solutions: > 1. offer utils that convert a plan represented in string to Relnodes. > 2. use RelBuilder to build plans and does comparison. > > and then just maintain the backward compatibility of the solution. > > just my two cents. > > > -Rui > > > On Mon, Dec 30, 2019 at 12:20 PM Vladimir Sitnikov < > [email protected]> wrote: > > > The change improves slow tests from 80 min to 60, and the changes are > > minimal > > > > Vladimir > > > >
