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Relational Database is collection of interrelated data managed with their relations. Database holds both the structure (schema) of the relations and the data itself. These structures are usually called tables.
For example, a to represent people working in different organizations, we could have a Person table, an Organization table, and Works table. Person table would hold a unique identifier of each worker, along with other personal information. Organization table would hold a unique identifier of each organization, along with other information about that entity. Works table would hold the pairs of unique identifiers - one pair for each person working in one organization.
If a Person is never allowed to work in more than one Organization, we could avoid using the Works table and store the organization's identifier as a field within the Person table. That is called a foreign key.
For instance, we have a table with name student and we have a table with name courses. The tables have some attributes for student(student number-sid,student name-sname,student last name-slname,student department-sdep) and for course(course number-cid,course name-cname) etc. Here we can see relational database because students take courses and here we can create a new table with attribute (student number-sid,course number-cid) because many student can take many course.Ahmet Eralp KÜÇÜK.
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Relational Database matches data by using common characteristics found within the data set.
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Addendum:
While the above answer is what most people would consider a proper definition of a relational database, it is in fact not correct. The name "Relational Database" was coined by it's creator Dr. Edgar F. Codd in 1970 in his book titled "A Relational Model of Data for Large Shared Databanks". The new database model was based on two branches of mathematics; Set Theory and First Order Predicate Logic.
The name itself was derived from the term "relation" which is a part of Set Theory and in fact has nothing to do with the coincidence that there is usually one field in each table of a relational database that correlates with another field in another table (aka Foreign Key Relations). It is in fact entirely possible to create a relational database without any of these foreign keys.
- Dallas Caley
Reference: SQL Queries For Mere Mortals, by Michael J. Hernandez and John L. Viescas. Addison Wesley 2000.
Monica Abbott
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Is Excel an example of a relational database?
No. It is a spreadsheet application. You can do simple databases in it, but it is not designed to create complex databases like relational databases. To do that you would use an actual database application.
What has the author Chao-Chih Yang written?
Chao-Chih Yang has written: 'Relational databases' -- subject(s): Relational databases
What has the author David Maier written?
David Maier has written: 'The theory of relational databases' -- subject(s): Database management, Relational databases
What is the importance of relational database?
Importance of relational database----------------------------------------------Relational databases can be considered as stores of information grouped together logically. Relational databases are used in all data related jobs. Especially in today's world of information, relational databases have increased importance, since they are used to store, manage, and retrieve data in a managed, organised and logical way. More information on relational databases, and their importance, can be found in detail here: http://tinyurl.com/relationaldatabase
What has the author Stefan Stanczyk written?
Stefan Stanczyk has written: 'Theory and practice of relational databases' -- subject(s): Relational databases, Database management
What kind of database exist?
The two major commercial classes of database are; relational and non-relational. Example of non-relational databases include Informix c-isam and dbisam. The main relational databases are; MS SQL Server, Sybase, Oracle, Progress, mySQL.
Example of ralational databases?
Microsoft Access is a relational database.
Compare contrast relational databases object-relational databases and object-oriented databases Site an example or scenario where each type is best used?
A relational database is structure to recognize relations among information, and stores the information in tables. An object-oriented database focuses on presenting the information in the form of objects, to be used for object-oriented programming. Object-relational databases are a hybrid of the two, keeping relations stored but still keeping the object-type data. Relational databases are best for presentation of the data itself, while object-oriented databases are better for deriving new information from given information.
Database management the origin and its growth in sql?
E. F. Codd introduced the term in his seminal paper "A Relational Model of Data for Large Shared Data Banks", published in 1970. In this paper and later papers he defined what he meant by relational. One well-known definition of what constitutes a relational database system is Codd's 12 rules. However, many of the early implementations of the relational model did not conform to all of Codd's rules, so the term gradually came to describe a broader class of database systems. Relational databases, as implemented in relational database management systems, have become a predominant choice for the storage of information in new databases used for financial records, manufacturing and logistical information, personnel data and much more. Relational databases have often replaced legacy hierarchical databases and network databases because they are easier to understand and use, even though they are much less efficient. As computer power has increased, the inefficiencies of relational databases, which made them impractical in earlier times, have been outweighed by their ease of use. However, relational databases have been challenged by Object Databases, which were introduced in an attempt to address the object-relational impedance mismatch in relational database, and XML databases. http://en.wikipedia.org/wiki/Relational_... http://en.wikipedia.org/wiki/Relational_...
In relational databases tables are linked to each other through a?
common field
What is an example of a standard query language used in relational databases?
The standard query language for relational databases, as adopted by the American National Standards Institute (ANSI), is SQL, which is generally understood to be an abbreviation for "structured query language."
What has the author T H Merrett written?
T. H. Merrett has written: 'Relational information systems' -- subject(s): Relational databases
