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Database System Concepts
Database System Concepts

... Failures may leave database in an inconsistent state with partial updates carried out  Example: Transfer of funds from one account to another should either complete or not happen at all  Concurrent access by multiple users  Uncontrolled concurrent accesses can lead to inconsistencies  Example: T ...
Database systems database: a structured collection of data
Database systems database: a structured collection of data

... select * from books where author = "Flanagan"; select author, title from books where author like "F%"; select author, title from books order by author; select author, count(*) from books group by author; select author, count(*) as n from books group by author ...
CENG 352 Database Management Systems - COW :: Ceng
CENG 352 Database Management Systems - COW :: Ceng

... reports, insertions, deletions and modifications to its content • Concurrent Processing and Sharing by a set of users and programs – yet, keeping all data valid and consistent ...
Database System Concepts - Department of Systems Engineering
Database System Concepts - Department of Systems Engineering

... Failures may leave database in an inconsistent state with partial updates carried out  Example: Transfer of funds from one account to another should either complete or not happen at all  Concurrent access by multiple users  Uncontrolled concurrent accesses can lead to inconsistencies  Example: T ...
Database systems database: a structured collection of data
Database systems database: a structured collection of data

... select * from books where author = "Flanagan"; select author, title from books where author like "F%"; select author, title from books order by author; select author, count(*) from books group by author; select author, count(*) as n from books group by author ...
Entity Framework
Entity Framework

...  LINQ-to-SQL (Not used)  Both combine entity class mappings and code generation, SQL is ...
account-number - UCLA Computer Science
account-number - UCLA Computer Science

... (select customer-name,account-number from depositor, inserted where inserted.account-number = depositor.account-number) insert into loan values (inserted.account-number, inserted.branch-name, – inserted.balance) update account set balance = 0 from account, inserted where account.account-number = ins ...
Chapter 1
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Chapter 24 - Personal Web Pages
Chapter 24 - Personal Web Pages

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Entity Framework
Entity Framework

... Use the generated code You should place the EDM and therefore the generated code in a class library (dll-assembly). Then you can access the EDM from your data-tier, business-tier, persistent-tier, etc. When you access from another assembly remember to add a reference to your EDM assembly and to sys ...
Data modeling
Data modeling

... Can store current or historical data Can become independent if given an arbitrary identifier ...
Storage and Disks
Storage and Disks

...  Primary medium for the long-term storage of data; typically stores entire database.  random-access – possible to read data on disk in any order, unlike magnetic tape  Non-volatile: data survive a power failure or a system crash, disk failure less likely than them ...
Oracle Database 11g Administration
Oracle Database 11g Administration

...  Starting and stopping the database  Mounting and opening the database with SQL*Plus  Authenticating connections having SYSDBA privilege  Closing the database and shutting down the instance Automating Database Management  The Oracle Enterprise Manager architecture  Navigating the graphical int ...
Introduction to Database Systems
Introduction to Database Systems

... oriented vs data oriented) – at the “low end”: scramble to webspace – at the “high end”: scientific applications Datasets increasing in diversity and volume. – Digital libraries, interactive video, Human Genome project, EOS project – ... need for DBMS exploding DBMS encompasses most of CS – OS, lang ...
Lecture Note 5
Lecture Note 5

... FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' (shipNum, shipName, yearBuilt, capacity) BEGINDATA "001","Century","1986","2000" "002","Galaxy","1989","1500" "003","Horizon","1992","1600" "004","Infinity","1995","2500" "005","Journey","1998","2500" "006","Mercury","2001","3000" ...
chapter_08__xid
chapter_08__xid

... – Most effective when done on a “data warehouse” (collection of diverse data from sources that one would not think of relating that is specifically structured for query and analysis) • Online analytical processing (OLAP): real-time analysis of data stored in databases • Structured query language (SQ ...
Using SQL on Nonrelational Databases
Using SQL on Nonrelational Databases

... not. In a network. a set with absent related records is caned an -emply set. Thes'J are quite common. In the sample dataoase, there are !Severa~ examples o-f misSing ,r'8GQrds. The structures for Cox and Dixon are incomplete because there are' no ACT records. The- structure for Adams is incomplete b ...
VisDB:Multidimensional Data Exploration Tool
VisDB:Multidimensional Data Exploration Tool

... It is possible for the user to assign two attributes to the axes and the system will arrange the relevance factors according to the directions of the distance of the data point from the selection predicate. With this method it is possible to provide better feedback to the user. However, we may not b ...
slides - Temple University
slides - Temple University

... Possibly many candidate keys (specified using UNIQUE), one of which is chosen as the primary key. “For a given student and course, CREATE TABLE Enrolled ...
11g General New Features
11g General New Features

... • Plan changes are automatically verified in maintenance window • Only comparable or better plans are used going forward ...
Introduction to Microsoft Access 2010
Introduction to Microsoft Access 2010

... The Quick Access toolbar is present on the top left corner of the Access window. It has buttons for commands that are used frequently. Define Ribbon. The Ribbon contains multiple tabs, each with several group of commands. Some tabs appear only when you work with certain objects like Forms. These tab ...
Chapter 9: Object-Relational Databases
Chapter 9: Object-Relational Databases

... and constructs to deal with added data types. • Allow attributes of tuples to have complex types, including non-atomic values such as nested relations. • Preserve relational foundations, in particular the declarative access to data, while extending modeling power. • Upward compatibility with existin ...
DATABASE ENVIRONMENT
DATABASE ENVIRONMENT

... – How to retrieve this? (record by record) ...
Querying Database - San Francisco State University
Querying Database - San Francisco State University

... • Projection operation defines a vertical subset of a table and retrieves only the specified fields. • Example: Customer table: CID, Cname, City, Rating – Create a query to show CID, Cname, Rating – Create a query to show CID, Cname, City ...
slides
slides

... WHERE condition1 – which records (i.e., rows) to delete AND condition2 etc – you can combine more than one condition using AND or OR e.g.: DELETE * FROM Products WHERE ProdID=“bongos” ...
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Relational model



The relational model for database management is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in 1969 by Edgar F. Codd. In the relational model of a database, all data is represented in terms of tuples, grouped into relations. A database organized in terms of the relational model is a relational database.The purpose of the relational model is to provide a declarative method for specifying data and queries: users directly state what information the database contains and what information they want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for answering queries.Most relational databases use the SQL data definition and query language; these systems implement what can be regarded as an engineering approximation to the relational model. A table in an SQL database schema corresponds to a predicate variable; the contents of a table to a relation; key constraints, other constraints, and SQL queries correspond to predicates. However, SQL databases deviate from the relational model in many details, and Codd fiercely argued against deviations that compromise the original principles.
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