Expressing and Optimizing Sequence Queries in Database Systems pdf

... determines how far the pattern should be advanced in the input, and ACM Transactions on Database Systems, Vol. 29, No. 2, June 2004. Expressing and Optimizing Sequence Queries in Database Systems • 295 —next( ... Transactions on Database Systems, Vol. 29, No. 2, June 2004. Expressing and Optimizing Sequence Queries in Database Systems • 309 WHERE A.Pa...

Ngày tải lên: 30/03/2014, 22:20

... demand site and flow requirement. 2. Runoff and infiltration from catchments, assuming no irrigation inflow. 3. Inflows and outflows of water for every node and link in the system. This includes ... of simulating operating rules. In AQUATOOL, operating rules are fixed and in WEAP they are defined as a combination of system states and hydrologic conditions. Both AQUATOOL...

Ngày tải lên: 05/09/2013, 14:58

... Key Words and Phrases: Engineering database systems, geometric modeling, object-oriented database systems INTRODUCTION Motivation The last few years have shown a rapid increase in the use ... engineering database systems investigated in the remainder of this section. 3.1 The (Pure) Relational Database Systems In the introduction to this paper we cited a few reasons...

Ngày tải lên: 07/03/2014, 23:20

... metho- dology by incorporating advanced techniques from software engineering, moving toward third-genera- tion systems by incorporating expert systems, and returning to interactive techniques ... algebraic and less geometric in nature, and we prefer to use a speci- fication in terms of the kind of structures we are accustomed to manipulating. 2 - Grafting o n expert syst...

Ngày tải lên: 08/03/2014, 18:20

... dominance checking, which can be expen- sive if the skyline contains numerous points. In order to speed up this process we insert the skyline points found in a main-memory R-tree. Continuing ... Skyline Computation in Database Systems • 59 Fig. 10. Incremental skyline maintenance for insertion. Fig. 11. Incremental skyline maintenance for deletion. skyline (of the whole dataset). I...

Ngày tải lên: 23/03/2014, 16:21

... that minimizing superfluous context switches (i.e. avoiding prematurely scheduling threads blocked on mul- tiple contentions) is key to maintaining acceptable perfor- mance in deterministic systems ... shifting between execution models presents an intriguing future avenue of research. 3. THE CASE FOR NONDETERMINISM Before making the case for disallowing nondeterministic behavior in data...

Ngày tải lên: 30/03/2014, 13:20

... block-nested-loops, and sort-merge join. We plan to implement hash join in the future and study its im- pact on our techniques. Queries: We are interested in queries (particularly joins) involving compressed ... Data compression support in databases. In Proc.ofVLDB, pages 695–704, 1994. [20] T. J. Lehman and M. J. Carey. Query processing in main memory database management...

Ngày tải lên: 30/03/2014, 13:20

... raw-temp-readings where raw-temp-readings.sensorid = M and time between training-start and training-end observations select * from raw-temp-readings where raw-temp-readings.sensorid = M and time > training-end Figure ... handling incomplete information in databases. In PODS, 1989. [16] S. Grumbach, P. Rigaux, and L. Segoufin. Manipulating interpolated data is easier than you tho...

Ngày tải lên: 30/03/2014, 13:20

... simplifying certain interacon objects make more sense than agging important pieces of informaon within them? Do you have enough informaon to usefully answer these and other envisioning ques- ons? ... your team is striving to mediate? How do the mindsets and constraints inherent in dierent tasks or larger acvies drive work- ers to adopt dierent frameworks for thinking and...

Ngày tải lên: 16/02/2014, 07:20

... deposit and lending interest rates. These findings, more generally support the use of RRs as a policy instrument in an inflation-targeting regime in terms of their effectiveness in reinforcing ... measures in Latin America is reported in Table 1. Despite their increasing use, the effectiveness of macroprudential policies in leaning against credit growth and in protectin...

Ngày tải lên: 06/03/2014, 04:21