Showing entries 1 to 1
Displaying posts with tag: tree traversal (reset)
GRAPH engine – Mk.II

The GRAPH engine allows you to deal with hierarchies and graphs in a purely relational way. So, we can find all children of an item, path from an item to a root node, shortest path between two items, and so on, each with a simple basic query structure using standard SQL grammar.

The engine is implemented as a MySQL/MariaDB 5.1 plugin (we’re working on a 5.0 backport for some clients) and thus runs with an unmodified server.

Demo time! I’ll simplify/strip a little bit here for space reasons, but what’s here is plain cut/paste from a running server, no edits

-- insert a few entries with connections (and multiple paths)
insert into foo (origid, destid) values (1,2), (2,3), (2,4), (4,5), (3,6), (5,6);
-- a regular table to join on to
insert into people values (1,"pearce"),(2,"hunnicut"),(3,"potter"), …
[Read more]
Showing entries 1 to 1