Class 11 Database notes Advantages of Using SQL (Structured Query Language)

 Advantages of Using SQL (Structured Query Language)

1. Standardized Language: SQL is an ANSI and ISO standard language for database queries, providing a uniform platform for database management across different systems.

2. Efficient Data Retrieval: SQL allows for efficient data retrieval using complex queries, joins, and aggregations, enabling quick access to the required information.

3. High-level Language: SQL is a high-level, declarative language, meaning that you specify what you want, not how to get it. The database engine optimizes the query for you.

4. Versatility: SQL can be used for various types of databases, including relational, NoSQL, and NewSQL databases.

5. Scalability: SQL databases are scalable, making them suitable for handling large volumes of data.

6. Security: SQL provides strong security features, including roles, permissions, and views, to protect sensitive data.

Data Definition Language (DDL)

Advantages:

1. Schema Definition: DDL commands like CREATE, ALTER, RENAME and DROP define and modify the database structure, such as tables, indexes, and schemas.

Data Manipulation Language  (DML)

Advantages:

1. Data Modification: DML commands like INSERT, UPDATE, SELECTand DELETE are used to modify the data within the database.

Introduction to MySQL

MySQL is an open-source relational database management system (RDBMS) that uses SQL for database access. It is widely used due to its reliability, ease of use, and strong community support.

Key Features:

• Cross-platform: Runs on various platforms, including Windows, Linux, and macOS.
• Security: Provides robust security features such as user authentication, encryption, and access control.
• Performance: Optimized for high performance, handling large-scale web applications efficiently.

Creating a Database using MySQL

To create a database in MySQL, you can use the following SQL command:

CREATE DATABASE database_name;

Example:

CREATE DATABASE school;

Data Types in MySQL

MySQL supports various data types categorized into different groups:

1. Numeric Data Types:

   • INT: Integer type, e.g., INT, TINYINT, SMALLINT, MEDIUMINT, BIGINT.
   • FLOAT: Floating-point number, e.g., FLOAT, DOUBLE.
   • DECIMAL: Fixed-point number.

2. String Data Types:

   • CHAR: Fixed-length string.
   • VARCHAR: Variable-length string.
   • TEXT: Large string of text.

3. Date and Time Data Types:

   • DATE: Date format YYYY-MM-DD.
   • DATETIME: Date and time YYYY-MM-DD HH:MM:SS.
   • TIMESTAMP: Timestamp for recording the time of an event.

4. Binary Data Types:

   • BLOB: Binary Large Object, used for storing binary data such as images or multimedia.

5. Boolean Data Type:

• BOOLEAN: Stores TRUE or FALSE values.