--
发件人：Stamatis Zampetakis
日 期：2020年03月28日 01:47:30
收件人：
主 题：Re: Join Pruning/Rewrites
Hi Chris,
I think your question is equivalent to the following:
Does Calcite perform query minimization [1, 2] ?
I don't remember seeing any part in Calcite that does this at the moment
Hi Chris,
I think your question is equivalent to the following:
Does Calcite perform query minimization [1, 2] ?
I don't remember seeing any part in Calcite that does this at the moment
but I may be wrong.
In general the problem is NP-Hard, so no hope for treating it entirely for
arbitrary
A note I forgot to mention earlier is that I’m starting with a RelBuilder...
On Fri, 27 Mar 2020 at 15:59, Chris Channing
wrote:
> Hey Folks,
>
> Is it currently possible to have Calcite optimize-away unnecessary joins?
> The case I'm thinking of is where (hopefully the formatting holds up!):
>
Can you give an example using real-ish tables eg customers, products, orders.
And show the 2 sql statements that you allege to be equivalent. I have a
feeling that it’s important which join keys you use.
Julian
Ps also please join the list so that you get replies.
> On Mar 27, 2020, at
