Ø Data :
It is raw fact through which an object can‘t be identified.
Ex – employee no. name, salary of an employee are individually known as one one data
Ø Information
Organized collection of related data is known as information through which an object can be clearly identified. It is raw fact through which an object can be identified.
Ex – employee no. name, salary of an employee are individually known as one one data
Ø Data file
Organized collection of related information is known as a data file. Ex – sales dept, purchase dept, admin dept of a particular company individually maintains their data file.
NOTE
Through data is a raw fact through which an object can‘t be identified but it minimum requirement of data base. Ø Why data base ?
Data is maintained to keep track on object day to day traction. The advantage of data base management is to know assets / liability, profile /loss of an organization. Database has no scope that means it can be implemented on small scale corporate house.
Ø MEDIAS TO MAINTAIN DATABASE
To maintain database three diff Medias are available a) Paper or cabinet file
b) Spread sheet c) DBMS: ” It is basically software responsible to store, retrieve and modify the data of a database on user request.”
Till date computer has seen 4 types of databases.
1. Network
2. Hierarchical 3. Relation
4. Object relation
The primary jobs of above database are same i.e. to store data, but there are divided into 4 diff categories depending on their storage architectures. These databases are also known as data models or data architectures.
Depending on the support to the databases DBMS is also categorized into 4 diff types namely
1. NDBMS
2. HDBMS 3. RDBMS
4. ORDBMS
DBMS RDBMS ORDBM
FoxPro oracle 6, 7 oracle 8
Dbase access oracle 8i
FoxBASE SQL server oracle 9i
Paradox db2, Informix oracle 10g
RDBMS is not software typically rather than it is a concept or theory developed by a scientist called DR JOHN E.F.CODD the prescribed 12 diff rules for relation architecture. Any database that support 6 or more then 6 rules will know as relational database and to manipulate them software has to be RDBMS type.
It any support less than 6 rules will known as general database and to manipulate it DBMS software is available.
Ø Def(RELATIONAL DATABASE)
“It is nothing but the organized collection of two dimensional tables or relations”.
EMP
EMP no 1 2 3 4
Name a b c d
Sal. 5000 6000 4550 7550
Above graphics shows the relational models of architecture. In relation model of architecture always data present in diff. diff. modules, each module is known as a table has a relation with another one.
The primary advantage of relational architecture is supports less data redundancy and more data security.
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