Re: Patch for removng unused targets

> From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]

> "Etsuro Fujita" <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp> writes:
> > Sorry for the delay. I've reviewed the patch. It was applied
> > successfully, and it worked well for tests I did including the example
> > you showed. I think it's worth the work, but I'm not sure you go
> > about it in the right way. (I feel the patch decreases code
> > readability more than it gives an advantage.)
>
> One thought here is that I don't particularly like adding a field like
> "resorderbyonly" to TargetEntry in the first place. That makes this
> optimization the business of the parser, which it should not be; and
> furthermore makes it incumbent on the rewriter, as well as anything else
> that manipulates parsetrees, to maintain the flag correctly while
> rearranging queries. It would be better if this were strictly the
> business of the planner.

Okay. I would like to investigate a planner-based approach that would not
require the resorderbyonly field.

Thanks,

Best regards,
Etsuro Fujita