The Formal Description and Implement Approach of Recursive Query in Tree-Like Structure
LI Yunlan · Journal of Changsha University · 2004
Recursive query provides a very flexible and effective processing way for relational data involving multiple hierarchical structure. This paper describes formally recursive query with relational algebra and datalog rule based on logical, and also discusses the least-fixed point computation equation and the principle of stratified negation in recursive query. Further, the paper analyzes the SQL3 approach to recursion program and restricted forms of query in detail.