J. Van den Bussche, D. Van Gucht, and G. Vossen. Reflective programming in the relational algebra. Journal of Computer and System Sciences, 52(3):537--549, June 1996.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....given operations T 1 and T 2 the precondition P to guarantee that IF P THEN T 2 ELSE fail specializes T 1 . Then the result of the GCS algorithm can be rewritten as an expression involving these macros [7] The expressive power of reflection in the relational datamodel has been investigated in [14]. 4 Conclusion In this paper we did the first step towards an integration and comparison of two alternative approaches to integrity enforcement in relational databases. The popular approach using rule triggering systems (RTSs) turns out to be powerfull for inclusion and functional dependencies ....

J. Van den Bussche, D. Van Gucht, G. Vossen, Reflective Programming in the Relational Algebra, in Proc. PODS '93 , pp. 17-25.

....the reduction takes only polynomial time. It remains open whether this can be improved. There has been little previous formal work on reflection in database languages. Ross introduces in [R92] relational algebra with a limited form of reflection, allowing relations that contain relation names. In [VVV93], relational algebra is augmented with the ability to dynamically generate and evaluate queries encoded in relations, yielding Reflective Relational Algebra (RRA) The results provide a connection between RRA and relational algebra with bounded looping (introduced in [Ch81] As a corollary, the ....

J. Van den Bussche, D. Van Gucht and G. Vossen. Reflective programming in the relational algebra. In Proc. 12th ACM SIGACT-SIGMOD-SIGART Symp. on Principles of Database Systems, pages 17-25, 1993.

....the specification of data independent views, a language that permits quantification over schema labels is needed. Many higher order languages that include some form of quantification over schema constructs have been proposed. These include multi database languages [27] logics [11, 23] algebras [33, 17], and objectcreate view v2 (co, date, price) as create view v3 (co, date, price) as select A, T.date, T.A from s3: stock A, S3: stock T where A = date select R, T.date, T.price from s2 R, R T ( select coA , date, price from coA select coB , date, price from coB select coC , date, price from ....

D. Van Gucht J. Van den Bussche and G. Vossen. Reflective Programming in the Relational Algebra. In Proc. of the ACM Symp. on Principles of Database Systems (PODS), pages 17--25, 1993.

....it cannot express schema independent queries. Lastly, in approach (3) how to integrate the new models and query languages with a relational system is unclear. A novel approach that effectively addresses inexpressiveness, schema independence, etc. studied by Van den Bussche, Van Gucht, and Vossen [18], involves extending the query language with reflection mechanisms [12, 13, 14] reification, the association of data with the meaning of a program, and evaluation, the association of the meaning of a program with data. Essentially, adding reflection to a programming language enables that language ....

....introducing new data structures to SQL. In the field of databases, storing programs as data was initially investigated by Stonebraker et al. [15, 16] where they proposed a system that allowed programs to be stored as strings in tuple components and executed dynamically. Van den Bussche et al. [18] took this one step further by not only encoding programs as data, but also allowing manipulation of these encodings before evaluation. The true power of reflection comes from this manipulation of the encodings that gives a program the ability to examine its own state and modify its own ....

[Article contains additional citation context not shown here]

Van den Bussche, J., Van Gucht, D., and Vossen, G. Reflective programming in the relational algebra. In Proceedings of the Twelfth ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, Washington, D.C. (May 1993), pp. 17--25.

.... of the relation model have always been a popular research topic (e.g. 13, 15, 2, 11, 5] 2 Analogous conservative extension properties are known for complex object databases [17, 26, 23] and spatial databases [16] The present paper is a follow up on an earlier paper by three of us [25]. There, we studied the expressive power of evaluating stored relational algebra programs in a completely untyped setting. Relational algebra programs were encoded in data relations, and the standard operators of the relational algebra were used to manipulate these program relations . This ....

J. Van den Bussche, D. Van Gucht, and G. Vossen. Reflective programming in the relational algebra. Journal of Computer and System Sciences, 52(3):537--549, June 1996.

....(foo s schema may have changed) i.e. Bob may have to adapt his query to the current schema. We will call this phenomenon the meta data dependence problem of relational query languages. In recent years, several papers have appeared in the literature that address the meta data dependence problem [11, 10, 4, 16, 12, 26, 9]. The solutions proposed there augment the query language with mechanisms that allow it to query both meta data and ordinary data. In Section 4.4, we will review these papers. Here we only want to state that the solutions advocated in [11, 10, 4] though elegant, are embedded in very powerful ....

....dependence problem while remaining in the low data complexity class. This approach, however, allows untyped relational queries, thereby moving away from the conventional definition of relational query [5] as it is used in relational database management systems. Finally, the solution advocated in [26], which relies on adding reflection to the query language and is sufficiently powerful, is too complex for the task at hand. In this paper we present another approach to overcome the meta data dependence problem in relational data processing. The key insight is to retain the meta data data ....

[Article contains additional citation context not shown here]

J. Van den Bussche, D. Van Gucht, and G. Vossen. Reflective programming in the relational algebra. In Proc. Twelth PODS , 1993, pp. 17--25.

No context found.

Van den Bussche, J., Van Gucht, D. and Vossen, G. (1993), Reflective programming in the relational algebra. In Proceedings of the 12th ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, 1993.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC