I have an assignment to find the shortest possible path between two people in a table. The table is Company(company_name, job, name), all of them not null, but none of them unique (primary key is the combination of all three values).
I'm supposed to use a recursive select query to find the shortest path between (for example) Bob Ross and Celine Dion. I know Bob is director of Painters, the manager of Painters is Carl, Carl is also an administrator in Sunny-D, and the director for Sunny-D is Celine Dion. So every name and company is a node, and the lines connecting them are the jobs. I'm not very good in SQL (we use PostgreSQL), and on top of that, I'm terrible at recursion, so if anyone could point me the right direction, I'd very much appreciate it.
What I have so far:
WITH RECURSIVE path(company_name, job, name, step) AS ( SELECT c.company_name, c.job, c.name, 1 FROM Company c WHERE person = 'Bob Ross' UNION ALL SELECT p.company_name, p.job, p.name, c.step+1 FROM path p JOIN Company c ON p.person = c.person WHERE c.person = 'Celine Dion' ) SELECT * FROM path;
I don't really know what to put in the recursive step where clause, or if I'm even joining them correctly