Folks, I agree with Nikolay, the idea of replacing the H2 engine with the most suitable one is reasonable. But since such change is major we should have a strong argumentation on it even for members with are working outside the SQL-team.
I think it is really necessary to have: 1. The list of issues related to the current engine (H2) which from different points of view and for different developers must seem unsolvable. For example, `... the H2 execution plan is hard-wired with H2 internals and can't be easily transformed` seems doesn't have a strong technical argumentation. After this step, we should have a clear understanding that the engine change is required. 2. Why only the Apache Calcite? It seems to me we should have a table with a comparison of different engines with the pros and cons of each other. A brief search shows me that we may have a few options here. After this step, we should have a clear understanding of why we choose this dependency prior to another. 3. We should also have a migration decomposition and step by step actions to do. I haven't found such a decomposition on IEP-37 page. Do we have one? What the implementation phases will be? What components will be changed? What a new API would be and would it be? What problems we are expecting e.g performance degradation on prototype implementation? `Risks and Assumptions` topic doesn't seem to be a good described. After this step, we should have a clear and obvious a new feature implementation plan. Let's have a strong technical discussion. On Fri, 27 Sep 2019 at 15:17, Nikolay Izhikov <nizhi...@apache.org> wrote: > > Hello, Roman. > > All I see is links to two tickets: > > IGNITE-11448 - Open > IGNITE-6085 - Closed > > Other issues described poorly and have not ticket links. > We can't discuss such a huge change as an execution engine replacement with > descrition like: > > "No data co-location control, i.e. arbitrary data can be returned silently" or > "Low control on how query executes internally, as a result we have limited > possibility to implement improvements/fixes." > > I think we need some reproducer that shows issue. > Tech details also should be added. > > Let's make these descriptions more specific. > Let's discuss how we want to fix them with the new engine. > > > В Пт, 27/09/2019 в 15:10 +0300, Roman Kondakov пишет: > > Hello Nikolay, > > > > please see IEP--37 [1]. Issues are there. > > > > > > [1] > > https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=130028084 > > > >
