UNIT-3 CLASS XII

UNIT III: DATABASE MANAGEMENT

Database Concepts: Introduction to database concepts and its

need.

Relational data model: Concept of domain, relation, tuple, attribute,

degree, cardinality, key, primary key, candidate key, alternate key

and foreign key;

Structured Query Language:

General Concepts: Advantages of using SQL, Data Definition

Language and Data Manipulation Language;

Data Types: number / decimal, character / varchar / varchar2, date;

SQL commands: CREATE TABLE, DROP TABLE, ALTER

TABLE, UPDATE ....SET...., INSERT, DELETE; SELECT,

DISTINCT, FROM, WHERE, IN, BETWEEN, LIKE, NULL / IS

NULL, ORDER BY,GROUP BY, HAVING;

SQL functions: SUM ( ), AVG ( ), COUNT ( ), MAX ( ) and MIN ( );

Joins: equi-join and natural join

Interface of Python with an SQL database

- Connecting SQL with Python

- Creating Database connectivity Applications

- Performing Insert, Update, Delete queries

- Display data by using fetchone(),fetchall(),rowcount