alamb commented on pull request #605: URL: https://github.com/apache/arrow-datafusion/pull/605#issuecomment-866862804
@houqp The approach we seem to be taking is to try and keep the information about where a column came from in a join -- e.g. that a output DF field could be referred to as either `f1.foo` or `f2.foo` for example, which is getting complicated It seems like a core challenge is in the semantics of the `*` expansion in `select * from ...` type queries which varies depending on type of join. Have you considered perhaps focusing in that area rather than trying to track the optional qualifiers through the plans? So for example, in a `f1 JOIN f1` have the output schema contain both `f1.foo` and `f2.foo` but then change the expansion of `*` to have somethign like `f1.foo as foo`? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
