Hi Liya, I had a look at the RelColumnMDOrigins and it is useful in determining which columns are from which table but still I am not sure how can I get the column information for TableScan without the rules. If you have any specific example where we have used this approach will be really helpful to me.
Thanks and regards Bhavya On Mon, Dec 21, 2020 at 5:53 PM Fan Liya <[email protected]> wrote: > Hi Bhavya, > > IMO, to solve the problem from a global view, the following steps needs to > be taken: > > 1. Generate a physical plan in the original way (without considering column > pruning in the table scan) > 2. Modify all the table scans in the plan with the RelColumnMDOrigins > utility (the details have been described above) > 3. Post process the plan with one of the following ways: > a) a plan visitor that adjusts other operators in the tree. > b) a light-weight planner (Hep or Volcano with limited rule sets) > > Run the query with the finally generated plan. > > Best, > Liya Fan > > > On Mon, Dec 21, 2020 at 3:33 PM Bhavya Aggarwal <[email protected]> > wrote: > > > Hi Fan, > > > > I looked at the class RelColumnMDOrigins and it is giving me the origin > of > > the column, but even if I want to take it as a global decision I am not > > sure how to proceed. Can you please elaborate on how to achieve this ? I > am > > literally stuck as I do not want to use so many rules as in any case I > have > > to pass these to the TableScan, even if the user does a select * from > > table, I need to add all those columns to the table scan. > > > > Regards > > Bhavya > > > > -- > > Your feedback matters - At Knoldus we aim to be very professional in our > > quality of work, commitment to results, and proactive communication. If > > you > > feel otherwise please share your feedback > > <https://forms.gle/Ax1Te1DDpirAQuQ8A> and we would work on it. > > > -- *Bhavya Aggarwal* CTO & Partner Knoldus Inc. <http://www.knoldus.com/> +91-9910483067 Canada - USA - India - Singapore <https://in.linkedin.com/company/knoldus> <https://twitter.com/Knolspeak> <https://www.facebook.com/KnoldusSoftware/> <https://blog.knoldus.com/> -- Your feedback matters - At Knoldus we aim to be very professional in our quality of work, commitment to results, and proactive communication. If you feel otherwise please share your feedback <https://forms.gle/Ax1Te1DDpirAQuQ8A> and we would work on it.
