That's an excellent idea. I would still like to distill the information into a talk, but it would be nice if the information was also in the code.
On Tue, Jun 24, 2014 at 10:53 PM, Sean Busbey <[email protected]> wrote: > Couldn't we add this kind of documentation to e.g. the MetadataSchema > class? > > Or some developer focuses architecture docs? > > > > On Jun 24, 2014 9:48 PM, "Eric Newton" <[email protected]> wrote: > > > > "<" means no end-row. It's the last tablet, which is often called the > default tablet. > > > > So, > > > >> 3p< ~tab:~pr \x00 > > > > > > You can decode this as a tablet covering (-inf, +inf) for tablet id 3p. > > > >> 3p;a ~tab:~pr \x00 > >> 3p;m ~tab:~pr \x01a > >> 3p;z ~tab:~pr \x01m > >> 3p< ~tab:~pr \x01z > > > > > > This table, id "3p" has splits: (-inf, a], (a, m], (m, z], (z, +inf). > "pr" stands for "end-row of previous tablet", which we often shorten to > "prevrow". Tilde's sort late in UTF8, which is important for some race > conditions when a table is splitting. > > > > I'm putting together a new presentation on the decoding of the metadata > tables. I need to get the presentation approved by my colleagues, so it's > going to be some time before it is ready. I would like to write a shell > Formatter that would make the metadata more more human friendly. > > > > If you have any other questions about the metadata table, please ask. > I'll make sure the answers are in the presentation. > > > > -Eric > > > > > > > > > > On Tue, Jun 24, 2014 at 10:21 PM, William Slacum < > [email protected]> wrote: > >> > >> < is a byte used for doing an ordering on rows that share the same > prefix. > >> > >> There was a presentation floating around on the specifics of the > metadata table at one point. I believe that helps tablet information sort > before the last tablet, which is suffixed with '~', to force it to sort > after the other tablets. We'll probably get an Eric or Keith email soon > laying down the law, but that's what I remember. > >> > >> > >> On Tue, Jun 24, 2014 at 9:57 PM, Dickson, Matt MR < > [email protected]> wrote: > >>> > >>> UNOFFICIAL > >>> > >>> When looking up rfile references in the metadata table we normally see > <tableid>;<range> for the rowid. I've noticed some rowids are > <tableid>< eg. 3p< > >>> > >>> Is this because the table is small and hasn't been split or some other > reason? > >> > >> > > >
