On Tue, 2010-08-03 at 10:12 +0100, Julian Foad wrote: > On Mon, 2010-08-02, I (Julian Foad) wrote: > > Hi Erik. > > > > Would you or anybody volunteer to draw a diagram of how these table rows > > look in various simple-ish WC states? > > Maybe I can help by drawing my best interpretation of it and getting > your feedback. I'll have a go.
Take a look at my attempt. I've started as textual tables rather than a visual diagram. <https://docs.google.com/document/edit?id=1IhLTs37OszES0dQ4f08RF9dl4VqvBoCrFHBaH6cFGbk#>. You're welcome to edit it directly if you email/IRC me and ask. - Julian > > I feel stupid saying this, but I haven't yet got much of an idea at all > > about how a set of database rows will represent a particular collection > > of repository nodes and local changes in the new scheme. I know roughly > > what the aim is (to be able to represent nested tree changes more > > flexibly), and I can read what elements of data will be stored in each > > table, but I am missing the part that says how those are connected. > > > > At this point we might as well assume it's a single DB - I think that > > will be clearest. > > > > Thanks. > > > > - Julian > > > > > > On Mon, 2010-07-12 at 23:23 +0200, Erik Huelsmann wrote: > > > After lots of discussion regarding the way NODE_DATA/4th tree should > > > be working, I'm now ready to post a summary of the progress. In my > > > last e-mail (http://svn.haxx.se/dev/archive-2010-07/0262.shtml) I > > > stated why we need this; this post is about the conclusion of what > > > needs to happen. Also included are the first steps there. > > > > > > > > > With the advent of NODE_DATA, we distinguish node values specifically > > > related to BASE nodes, those specifically related to "current" WORKING > > > nodes and those which are to be maintained for multiple levels of > > > WORKING nodes (not only the "current" view) (the latter category is > > > most often also shared with BASE). > > > > > > The respective tables will hold the columns shown below. > > > > > > > > > ------------------------- > > > TABLE WORKING_NODE ( > > > wc_id INTEGER NOT NULL REFERENCES WCROOT (id), > > > local_relpath TEXT NOT NULL, > > > parent_relpath TEXT, > > > moved_here INTEGER, > > > moved_to TEXT, > > > original_repos_id INTEGER REFERENCES REPOSITORY (id), > > > original_repos_path TEXT, > > > original_revnum INTEGER, > > > translated_size INTEGER, > > > last_mod_time INTEGER, /* an APR date/time (usec since 1970) */ > > > keep_local INTEGER, > > > > > > PRIMARY KEY (wc_id, local_relpath) > > > ); > > > > > > CREATE INDEX I_WORKING_PARENT ON WORKING_NODE (wc_id, parent_relpath); > > > -------------------------------- > > > > > > The moved_* and original_* columns are typical examples of "WORKING > > > fields only maintained for the visible WORKING nodes": the original_* > > > and moved_* fields are inherited from the operation root by all > > > children part of the operation. The operation root will be the visible > > > change on its own level, meaning it'll have rows both in the > > > WORKING_NODE and NODE_DATA tables. The fact that these columns are not > > > in the WORKING_NODE table means that tree changes are not preserved > > > accros overlapping changes. This is fully compatible with what we do > > > today: changes to higher levels destroy changes to lower levels. > > > > > > The translated_size and last_mod_time columns exist in WORKING_NODE > > > and BASE_NODE; they explicitly don't exist in NODE_DATA. The fact that > > > they exist in BASE_NODE is a bit of a hack: it's to prevent creation > > > of WORKING_NODE data for every file which has keyword expansion or eol > > > translation properties set: these columns serve only to optimize > > > working copy scanning for changes and as such only relate to the > > > visible WORKING_NODEs. > > > > > > > > > TABLE BASE_NODE ( > > > wc_id INTEGER NOT NULL REFERENCES WCROOT (id), > > > local_relpath TEXT NOT NULL, > > > repos_id INTEGER REFERENCES REPOSITORY (id), > > > repos_relpath TEXT, > > > parent_relpath TEXT, > > > translated_size INTEGER, > > > last_mod_time INTEGER, /* an APR date/time (usec since 1970) */ > > > dav_cache BLOB, > > > incomplete_children INTEGER, > > > file_external TEXT, > > > > > > PRIMARY KEY (wc_id, local_relpath) > > > ); > > > > > > > > > TABLE NODE_DATA ( > > > wc_id INTEGER NOT NULL REFERENCES WCROOT (id), > > > local_relpath TEXT NOT NULL, > > > op_depth INTEGER NOT NULL, > > > presence TEXT NOT NULL, > > > kind TEXT NOT NULL, > > > checksum TEXT, > > > changed_rev INTEGER, > > > changed_date INTEGER, /* an APR date/time (usec since 1970) */ > > > changed_author TEXT, > > > depth TEXT, > > > symlink_target TEXT, > > > properties BLOB, > > > > > > PRIMARY KEY (wc_id, local_relpath, oproot) > > > ); > > > > > > CREATE INDEX I_NODE_WC_RELPATH ON NODE_DATA (wc_id, local_relpath); > > > > > > > > > Which leaves the NODE_DATA structure above. The op_depth column > > > contains the depth of the node - relative to the wc root - on which > > > the operation was run which caused the creation of the given NODE_DATA > > > node. In the final scheme (based on single-db), the value will be 0 > > > for base and a positive integer for WORKING related data. > > > > > > In order to be able to implement NODE_DATA even without having a fully > > > functional SINGLE_DB yet, a transitional node numbering scheme needs > > > to be devised. The following numbers will apply: BASE == 0, > > > WORKING-this-dir == 1, WORKING-any-immediate-child == 2. > > > > > > > > > Other transitioning related remarks: > > > > > > * Conditional-protected experimentational sections, just like with > > > SINGLE_DB > > > * Initial implementation will simply replace the current > > > functionality of the 2 tables, from there we can work our way through > > > whatever needs doing. > > > * Am I forgetting any others? > > > > > > Bye, > > > > > > Erik. > > > > > >
