[aragot]

I've had positive experience with Postgresql, but I haven't personnaly witnessed how it behaves in production. In my opinion there aren't good alternatives to a recursive query:

- Send one request for each level of hierarchy? Worst of all.

- Stored procedure? I don't think it would be optimised compared to a recursive query.

See also: http://stackoverflow.com/questions/5861272/postgresql-with-r...

[ximeng]

Changing data structure is one approach:

http://stackoverflow.com/questions/935098/database-structure...