Updates from Simon Riggs:

Updates from Simon Riggs:

<   that can spam more than one table.
>   that can span more than one table.
239c239
<   rather than just col1
>   rather than just col1; also called skip-scanning.
641c641,642
< * Add free-behind capability for large sequential scans [fadvise]
> * Allow free-behind capability for large sequential scans, perhaps using
>   posix_fadvise() [fadvise]