* Gurjeet Singh (
singh.gurjeet@gmail.com) wrote:
> Bruce points out the even simpler case is to build several indexes in
> parallel over the same scan.
>
> I thought I had posted a patch to that effect long back, but upon searching
> my emails apparently I forgot about the patch.
>
> Attached is the patch that I developed in Nov. 2010, so expect a lot of bit
> rot. I had tried to make it elegant, but I have to admit its a hack. This
> patch does not imply that it is using any kind of parallelism, the context
> in which that above statement was made. It just helps to avoid scanning the
> same relation multiple times. I performed some tests on it and AFAICR, this
> did not produce a net win. But those tests may have been performed in a
> virtual machine and not on a bare metal, I forget.
I'm not too surprised that it didn't help all that much since you're