create collection in database mongodb

Ngày tải lên: 29/03/2014, 16:20

Ngày tải lên: 20/06/2014, 08:20

... could be obtained through mining or just from in- formation retrieval. Data mining is an important tool in making the web more intelligent. That is, data mining may be used to mine the data on ... Publisher Created in the United States of America Visit Springer's eBookstore at: http://ebooks.springerlink.com and the Springer Global Website Online at: http://www.springeronline.com Berlin ... computa- tional origins and information systems engineering aspects have received scant attention. The development within the GRID community of the W3C-inspired OGSA indicates a willingness to move in a direction...

Ngày tải lên: 14/12/2013, 15:15

... and enabling a single linear access of the upper-level index for any query point. In addition, to avoid rollback operations in the lower-level index, we try to maintain each grid cell in a size ... Energy-Conserving Air Indexes for Nearest Neighbor Search 51 Fig. 1. Data and Index Organization Using the Interleaving Technique for broadcasting along with the data objects [8]. By first examining the index information ... spatial index over object locations. Indexing Queries. The second centralized approach to processing spatial continuous queries on moving objects is by indexing queries. In this approach a spatial index,...

Ngày tải lên: 14/12/2013, 15:15

... minimize the information loss in moving from clustering to clustering This information loss is given by We can also view the information loss as the increase in the uncertainty. Recall that Since H(A) ... Constrained Indexing and Query Indexing are proposed for efficient evaluation of this kind of queries at a central location. Several other indexing structures and algorithms for handling moving ... 69-84. Bradley, P., Fayyad, U., & Reina, C. (1998). Scaling Clustering Algorithms to Large Databases. In proceedings of the Int’l Conference on Knowledge Discovery and Data Mining. New York, NY, Aug 27-31....

Ngày tải lên: 14/12/2013, 15:15

... is based upon ciphertext, while, in the second, the intermediate index is based upon plaintext and the final index is obtained by encrypting the intermediate index. Based upon characteristics ... xor-ing them) to obtain ciphertext. Decryption involves reversing the process: combining the key-stream with the ciphertext to obtain the original plaintext. Along with the initial encryption key, additional ... example, in a movie database, we may be interested in discovering clusters of directors or actors, which in turn could help in improving the classification of movie tuples. Given the joint distribution...

Ngày tải lên: 14/12/2013, 15:15

... Preserving Data Mining 187 We maintain the total number of records in that group. This number is denoted by We make the following simple observations: Observation 1: The mean value of attribute in ... predicates in between and not involving prefix-matching, whereas with or it is the number of equality predicates in between and a constant or between and a constant not involving prefix-matching. Matrices ... appearing in A move from is done by first randomly extracting a predicate pred from Pred. Let and be the containers involved in pred (for instance pred makes an equality comparison, such as or an inequality...

Ngày tải lên: 14/12/2013, 15:15

... relational databases into an XML format or to store the information in an XML object in a relational database, increasing the cost of e-business development. Moreover, specifying the mapping in the ... Experiences. In Proc. of the Int. Conf. on Very Large Databases (VLDB’02), Hong Kong, China, 2002 D. Kossmann, F. Ramsak, S. Rost. Shooting Stars in the Sky: An Online Algorithm for Skyline Queries. In ... DB-to-XML mapping, into several modified mappings in order to support clients that require various por- tions of the mapping-defined data. Mapping rewriting has the effect of reducing the amount...

Ngày tải lên: 14/12/2013, 15:16

... environment. 5.3 Phonetic Indexing We now outline a phonetic indexing technique that may be used for accessing the near- equal phonemic strings, using a standard database index. We exploit the following two facts ... extending the approximate indexing techniques outlined in [1, 21] for creating a metric index for phonemes. We are working on an inside-the-engine implementation of LexEQUAL on an open-source database ... let us introduce the collinear relation between a point and two regions. Definition 9. A point P is collinear to two regions B and C, collinear(P, B, C), if there exists a line l intersecting...

Ngày tải lên: 14/12/2013, 15:16

... designing the annotation specifications, considering the specifics of data integrity constraint checking, and ascertaining the impact on particular tools remain challenging (and interesting) tasks. focuses ... watermark. Computing and Handling Cardinal Direction Information 335 Fig. 3. Polygon clipping 3 Computing Cardinal Direction Relations Typically, in Geographical Information Systems and Spatial Databases, ... (i.e., in Fig. 9), in the fourth case, we use the south line of and in the last case, we use the north line of In all cases, we use the edges of that fall in the tile of that we are interested in. ...

Ngày tải lên: 14/12/2013, 15:16

... between index nodes from corresponding trees in a priority queue and recursively (top-down) refining the search. In this case, using histograms, one could perform, in addition to the type of pruning ... the minimum bounding constraint, which increases the general overlap. In memory, for instance, RS verifies four times more objects than AC. Point-Enclosing Queries. Because queries like “find ... queries like “find the database objects con- taining a given point” can also occur in practice (for instance, in a publish- subscribe application where subscriptions define interval ranges as attributes, and...

Ngày tải lên: 24/12/2013, 02:18

... projection pushing and join reordering in terms of the treewidth of the join graph. (Note that the focus in [28] is on projection pushing in recursive queries; the non-recursive case is not investigated.) While ... section. 5 Improvements Using Domain Information So far we have discussed in what cases we do not need to normalize queries in the containment test, and in what cases we can reduce the containment test to checking ... combine early projection and join reordering in an implementation of the bucket-elimination method from constraint satisfaction to obtain another exponential improvement. 1 Introduction The join...

Ngày tải lên: 24/12/2013, 02:18

... process of integrating it into computing systems, some prior approaches have been proposed to map MEMS-based storage into disk-like devices. Using disk terminology, a cylinder is defined as the ... up memory by deleting a set of nodes such that the increase in TSSENC (see definition in Equation 6) is minimized and a certain factor of the memory allocated for cost modeling is freed. allows ... instead of moving the media sled back to the coordinates of row 1 every time (thus introducing a new seek), the media sled is just turned around changing its moving direction, then the tips in...

Ngày tải lên: 24/12/2013, 02:18

... be computed quickly, in a single pass over the data tuples in in the (arbitrary) order of their arrival. At any point in time, our query-processing algorithms can combine the maintained collection of ... and since each iteration is actually a generalized bargaining step, using a nested bargaining within a bargaining will only increase the number of exchanged messages. 4 Experimental Study In order ... original query The problem of finding these plans is identical to the answering queries using materialized views [20] problem. In general, this problem is NP-Complete, since it involves searching...

Ngày tải lên: 24/12/2013, 02:18

... PJoin maintains an almost steady output rate whereas the output rate of XJoin drops. This decrease in XJoin output rate occurs because the XJoin state increases over time thereby leading to an increasing ... of XJoin. We differ in that no previous work incorporates both constraint-exploiting mech- anism and adaptivity into join execution logic itself. Unlike the k-constraint- exploiting algorithm, ... joins nor k-constraint-exploiting algorithms do. 6 Discussion: Extending PJoin Beyond Punctuations The current implementation of PJoin is a binary equi-join without exploiting window specifications...

Ngày tải lên: 24/12/2013, 02:18

... SIGMOD 1997. R. Pieringer et al: Combining Hierarchy Encoding and Pre-Grouping: Intelligent Grouping in Star Join Processing. ICDE 2003. F. Ramsak et al: Integrating the UB-Tree into a Database System ... defined by Definition 7, by finding all dead states in the intersection automaton of and to determine The set of states, as defined by Definition 8, can also be determined, in linear time, using ... 2000. B. Kane, H. Su, and E. A. Rundensteiner. Consistently updating XML documents using incremental constraint check queries. In Proceedings of the Workshop on Web Information and Data Management (WIDM’02),...

Ngày tải lên: 24/12/2013, 02:18

... to maintain than a LIST without any indices or the T-INDEX. For 10000 distinct values, the G-INDEX with 50 groups is faster than the T-INDEX and faster than maintaining a sliding window using ... watermark. On Indexing Sliding Windows over Online Data Streams 729 7 Conclusions and Open Problems This paper began with questions regarding the feasibility of maintaining sliding window indices. ... On Indexing Sliding Windows over Online Data Streams 723 Fig. 6. Maintenance of a BW ring index 5.3 Faster Deletion with Backward-Linked Ring Index (BW) The AUX method traverses the entire ring...

Ngày tải lên: 24/12/2013, 02:18

Ngày tải lên: 24/12/2013, 02:18

Ngày tải lên: 24/12/2013, 02:18

Ngày tải lên: 21/01/2014, 08:20