interfaces to data base systems

Ngày tải lên: 17/03/2014, 19:20

Ngày tải lên: 03/01/2014, 19:36

Ngày tải lên: 08/03/2014, 18:20

Ngày tải lên: 08/03/2014, 18:20

Ngày tải lên: 08/03/2014, 18:20

... có thể bị hủy bỏ ALTER DATABASE database_name { <add_or_modify_files> | <add_or_modify_filegroups> | <set_database_options> | MODIFY NAME = new_database_name | COLLATE collation_name }[;] Trong ... tạo. Cú pháp: CREATE DATABASE database_snapshot_name ON ( NAME = logical_file_name, FILENAME = ‘os_file_name’ ) [ , n ] AS SNAPSHOT OF source_database_name [;] RDBMS and Data Management/ Session ... là AdventureWorks RDBMS and Data Management/ Session 7/15 of 25 Nhóm tập tin và ghi vết giao dịch  Thêm nhóm tập tin trong khi tạo CSDL. Cú pháp: CREATE DATABASE database_name [ ON [ PRIMARY ]...

Ngày tải lên: 01/09/2012, 09:09

... hash-method often used an array structure to store database. If the database is too large, we can apply multi-level. By this deed, we are able to access database directly by using a key element instead ... use hash-based approach to reduce the implement size of database and quickly process. And based on these ideas, establish a small system to find association rules in transaction database. Contribution ... “hash-based approach to data mining” focuses on the hash-based method to improve performance of finding association rules in the transaction databases and use the PHS (perfect hashing and data...

Ngày tải lên: 15/04/2013, 21:33

... it hard to integrate databases and applications: • There are as many SQL dialects as there are database vendors. Almost all relational data- bases require the use of SQL to add data to tables ... motivated as follows: “Access to data varies depending on the source of the data. Access to persistent storage, such as to a database, varies greatly depending on the type of storage […] and the vendor ... advise you to look at how your application interacts with the database without regard to data- access code, JDBC, ORM tools, or Spring. You’ll find it easy to notice the pervasive effects of data- access...

Ngày tải lên: 05/10/2013, 04:20

Ngày tải lên: 04/11/2013, 20:15

... the codebook is the central problem of vector quantization. Scan the input data vector by vector and compress each vector v i by finding the codebook vector V j that is “nearest” v i . The index ... approach to lossy compression. The idea is to start with a finite list of N symbols S i and to modify each of the original data symbols to the nearest S i . For example, if the original data consists ... dictionary-based compression is to read the next data item D to be compressed, and search the dictionary for D.IfD is found in the dictionary, it is compressed by emitting a pointer that points to it...

Ngày tải lên: 14/12/2013, 15:15

... X to its successors in the tree (from left to right and bottom to top). If the immediate successor has frequency F + 1 or greater, the nodes are still in sorted order and there is no need to ... 268, and set it to (116, 265, s). This is why the index needs to be stored. 8. Hash(,115) → 270. Array location 270 is set to (115, 270, ). 9. Hash(a,32) → 268. A collision! Skip to the next available ... encoder has to use a buffer. Bits of the compressed data are entered into the buffer as they are being generated and are moved out of it at a constant rate, to be transmitted. It is easy to see intuitively...

Ngày tải lên: 14/12/2013, 15:15

... coefficients. This results in data items that are not identical to the original ones but are not much different. In practical applications, the data to be compressed is partitioned into sets of n items each ... to tell you to how many figures I carried these computations, having no other business at that time. —Isaac Newton To figure out the kind of compression achieved by arithmetic coding, we have to consider ... www.verypdf.com to remove this watermark. 136 4. Arithmetic Coding Today, we believe in the existence of atoms. If we start with a chunk of matter, cut it into pieces, cut each piece into smaller...

Ngày tải lên: 14/12/2013, 15:15

... compressed in a single left -to- right, top -to- bottom scan; (b) progressive mode where the image is compressed in multiple blocks (known as “scans”) to be viewed from coarse to fine detail; (c) lossless ... worldwide digital component video standard. Y is defined to have a range of 16 to 235; Cb and Cr are defined to have a range of 16 to 240, with 128 equal to zero. There are several YCbCr sampling formats, such ... This version of the DCT is applied to small parts (data blocks) of the image. It is computed by applying the DCT in one dimension to each row of a data block, then to each column of the result. Because...

Ngày tải lên: 14/12/2013, 15:15

... computer users long to realize that a computer can also store and process nonnumeric data. The term “multi- media,” which became popular in the 1990s, refers to the ability to digitize, store, and manipulate ... symbols. The decision is to exclude y, and this is done by setting array element excl[y] to the context index (i.e., to point to c). As long as the algorithm scans for matches to the same context ... audio file, we often want to listen to it while it is decompressed (in fact, we decompress it only in order to listen to it). This is why audio compression methods tend to be asymmetric. The encoder...

Ngày tải lên: 14/12/2013, 15:15

... to 127), the base value is set to xxxx40 (the seven LSBs are 64), and if the previous code point is in the range xxxx80 to xxxxFF (i.e., its seven least-significant bits are 128 to 255), the base ... “quantization” is to restrict a variable quantity to discrete values rather than to a continuous set of values.” If the data to be compressed is in the form of large numbers, quantization is used to convert ... work well for small data files. 1.5. RLE of images is based on the idea that adjacent pixels tend to be identical. The last pixel of a row, however, has no reason to be identical to the first pixel...

Ngày tải lên: 14/12/2013, 15:15

... decoder simply reads tokens and uses each offset to locate a string of text without having to know whether the string was a first or a last match. 1.10. Imagine a history book divided into chapters. One ... work well for small data files. 1.5. RLE of images is based on the idea that adjacent pixels tend to be identical. The last pixel of a row, however, has no reason to be identical to the first pixel ... DC) at its top-left corner and smaller elements (AC) elsewhere. The AC coefficients generally become smaller as we move from the top-left to the bottom-right corner and are largest on the top row...

Ngày tải lên: 14/12/2013, 15:15

... profits to be satisfactory—a large amount of costs cannot be incurred to produce a modest amount of revenue. Motorola managers acted to con- tain costs when they created Motorola Labs to spend ... com- municates data to managers. Control systems exist to guide organizations in achiev- ing their goals and objectives. They have four primary components: detectors, assessors, effectors, and a ... who had been accustomed to Digital sales reps Chapter 2 Introduction to Cost Management Systems 69 http://www.pg.com judgments about how to organize subunits and the extent to which authority...

Ngày tải lên: 18/12/2013, 09:13

... the logical storage medium for an OLAP database and are what users manipulate to access their data. Topic Objective To introduce OLAP database components. Lead-in OLAP databases are composed ... Structure N-dimensional Data structure N-dimensional Data structure Data Content Data Content Detailed and Summarized Data Detailed and Summarized Data Summarized Data Summarized Data Data Sources Data Sources Relational ... content, data sources, data retrieval, and business analysis capabilities. Data Storage Relational data marts and OLAP cubes differ in how they store data: ! Relational data marts store data...

Ngày tải lên: 21/12/2013, 19:15

Ngày tải lên: 24/12/2013, 06:17

... Strickland <strick@yak.net> datasurfsrv 461/tcp DataSurfSrv datasurfsrv 461/udp DataSurfSrv datasurfsrvsec 462/tcp DataSurfSrvSec datasurfsrvsec 462/udp DataSurfSrvSec 42 # David Arko ... <fquick@qualcomm.com> hp-collector 381/tcp hp performance data collector hp-collector 381/udp hp performance data collector hp-managed-node 382/tcp hp performance data managed node hp-managed-node ... Update-Based Routing Pro. aurp 387/udp Appletalk Update-Based Routing Pro. # Chris Ranch <cranch@novell.com> unidata-ldm 388/tcp Unidata LDM Version 4 unidata-ldm 388/udp Unidata LDM...

Ngày tải lên: 18/01/2014, 06:20