dados-hierárquicos

How to model a tree data structure using a relational database?

How to properly and efficiently define naturally tree-organized data in relational databases, considering the physical implic ... here is a way ( query ) more suitable for accessing (scanning/traversing) data structured in this way, an example would help.

How to return materials from a product or product levels with PL / SQL

I have a table that contains products and each product has other products that are used to manufacture. The products that are ... RT INTO MATERIAL (ID_PRODUCT_MATERIAL, PRODUCTION, ID_MATERIAL) VALUES (1,2,2), (1,2,3), (1,2,4), (2,1,9), (2,1,10), (3,1,8)