SQL over tree-type database?

Hello

Sorry, I am not a specialist in databases, so, perhaps, my question is simple or meaningless... We've got a relational database (PostgreSQL), which is currently VERY redundant. Ok, I know how to reduce the redundancy by splitting the table into several smaller (2-column in our case) ones. But, anyway the redundancy would only be decreased, and not removed completely, and building SQL-queries would become more difficult (nested selects, etc.), unless you can create something like a view on the top of several tables?... Anyway, the data naturally have tree-structure, so, ideally it should be kept that way (not sure if RDBMSs can perform such optimisation / redundancy removal automatically?), but I still want to be able to use SQL-queries. So, ideally, the data should be stored in a tree, but logically be representable as a table with rows spanning all tree-levels... Is this possible? and - if yes - how?

Thanks
Guennadi
___

Dr. Guennadi V. Liakhovetski
Department of Applied Mathematics
University of Sheffield, U.K.
email: G.Liakhovetski_at_sheffield.ac.uk Received on Sat May 05 2001 - 22:51:11 CEST