|Kraft, Tobias; Schwarz, Holger; Rantzau, Ralf; Mitschang, Bernhard: Coarse-Grained Optimization: Techniques for Rewriting SQL Statement Sequences. |
In: Proceedings of 29th International Conference on Very Large Data Bases (VLDB 2003), Berlin, September 9-12, 2003.
Universität Stuttgart, Fakultät Informatik.
S. 488-499, englisch.
Morgan Kaufmann, September 2003.
Artikel in Tagungsband (Konferenz-Beitrag).
|CR-Klassif.||H.2.4 (Database Management Systems)|
|Keywords||SQL; Query Optimization; OLAP|
Relational OLAP tools and other database applications generate sequences of SQL statements that are sent to the database server as result of a single information request provided by a user. Unfortunately, these sequences cannot be processed efficiently by current database systems because they typically optimize and process each statement in isolation. We propose a practical approach for this optimization problem, called ``coarse-grained optimization,'' complementing the conventional query optimization phase. This new approach exploits the fact that statements of a sequence are correlated since they belong to the same information request. A lightweight heuristic optimizer modifies a given statement sequence using a small set of rewrite rules. Since the optimizer is part of a separate system layer, it is independent of but can be tuned to a specific underlying database system. We discuss implementation details and demonstrate that our approach leads to significant performance improvements.
|Abteilung(en)||Universität Stuttgart, Institut für Parallele und Verteilte Höchstleistungsrechner, Anwendersoftware|
|Eingabedatum||30. Juni 2003|