Database Technologies
Overview
What is a Database
A Database Management System i.e. DBMS is a collection of interrelated data and a set of programs to access this data. The collection of data is called a database.
What is a Database System
A database system is consisting of two parts. (1) Database Management System: Program that organizes and maintains information. (2) Database Application: Program that lets us view, retrive and update information stored in the DBMS.
What are the Language Services of a Database Technology
The following are the Language Services of a Database Technology: (1) DDL- Data Definition: To Define & Store it. (2) DQL- Data Query: To Select, Order etc. (3) DML- Data Manipulation: To Insert, Update, delete, and Store. (4) DCL- Data Control: To Grant & Revoke Roles, To ensure Integrity & Accuracy of Data. (5) TCL- Transaction Control: To Commit, Rollback, Save Point.
DBMS VS RDBMS
RDBMS allows many users simultaneous access to the database. And DBMS permits only one person to access database at a given time. dBase, FoxPro etc. are the examples of DBMS whereas MS SqlServer, Oracle, MySql, Informix etc. are RDBMS. RDBMS satisfies codd’s rules, DBMS doesn’t. RDBMS data stored in the form of tables, DBMS data is stored in the form of rows & columns. RDBMS stores keys for everything and maintains/allows integrity, DBMS doesn’t.