SQL Tutorial Series

Introduction to SQL

• SQL: Structured Query Language
• Used to read or modify data in relational database management systems (DBMS) such as Oracle, MySQL, SQL Server.
• Data is stored in a tabular format (rows and columns).

Example Table: Student

• Columns (Attributes):
  • Role Number
  • Name
  • Age
  • Marks
  • Division
• Contains 6 records (rows of actual data).

SQL Functions

1. Create tables
2. Insert information
3. Update information
4. Retrieve information

SQL Statements

• SQL statements are called queries.
  • Used to read and write information.

Types of SQL Commands

1. Data Definition Language (DDL)

• Used for creating tables.
  • Specify table name and columns.
  • Define data types for each column (e.g., numeric for role number, string for name).
• Executes DDL command to create an empty table.

2. Data Manipulation Language (DML)

• Used for:
  • Inserting information
  • Updating existing information
  • Deleting information
• Example of update: Changing age from 13 to 12.

Tools for SQL

• Using Oracle Express Edition and SQL Server for this tutorial series.
• Instructions to download Oracle Express Edition:
  • Search for Oracle XE and download from the Oracle site.
• SQL Developer requires Java Development Kit (JDK).

Setup Steps

1. Install Oracle XE and SQL Developer.
2. Remember the password provided during installation for database connection.
3. Use SQL Developer instead of SQL command line console.
4. Create a desktop shortcut for ease of access.

First Time Opening SQL Developer

• Prompt to provide the path of JDK installation.
• Steps to create a database connection:
  • Open SQL Developer.
  • Go to Connections and add a new connection.
  • Provide:
    • Connection name (e.g., local sys)
    • Username (system)
    • Password (as provided during installation)
  • Test the connection.

Conclusion

• In the next tutorial, we will learn how to create tables and write SQL queries.
• Happy learning!