On 21 December 2015 at 12:54, Robert Haas <robertmh...@gmail.com> wrote:
> On Thu, Jul 9, 2015 at 4:49 PM, Jeff Janes <jeff.ja...@gmail.com> wrote: > > Is there anything in the below section which has been been implemented or > > rendered irrelevant by BRIN indexes? > > > > https://wiki.postgresql.org/wiki/Todo#Indexes > > > > "Consider smaller indexes that record a range of values per heap page, > > rather than having one index entry for every heap row" > > [ catching up on old threads ] > > BRIN is exactly this, isn't it? Well, moreso: it's a range of values > for a range of heap pages. > It's close, but not the same. BRIN is a summary index and so could never support uniqueness. It's also possible to have an index type that has a precise TID entry, yet a more compact format, which would then allow unique values. This would be similar to the way SQLServer compresses primary key indexes. -- Simon Riggs http://www.2ndQuadrant.com/ <http://www.2ndquadrant.com/> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services