Optimization on a case of type‐d nested query
Jiann‐Tsair Chen, Wei‐Pang Yang, Meichun Hsu · Journal of the Chinese Institute of Engineers · 1988
Nesting is an important feature in structure query languages (SQL) of the relational database. However, the nesting of query blocks sometimes results in bad performance while evaluating such a query if no effort is contributed to it. A new algorithm to transform a nested query into an equivalent one which is more efficient to process is presented in this paper. The correctness of the transform algorithm is shown as well as the complexity is analyzed in this paper.