SQL

SQL (Structured Query Language) is used to manage and manipulate relational databases. It allows users to store, retrieve, and analyze data efficiently.

RDBMS Basics

• A Relational Database Management System (RDBMS) organizes data into tables with relationships.
• Primary Keys uniquely identify each record in a table.
• Foreign Keys establish relationships between tables, ensuring data integrity.

Basic SQL Concepts

• SQL enables retrieving data based on conditions for analysis.
• It allows filtering records to fetch only relevant information.
• SQL queries can be integrated with Python Pandas for further data processing.

Advanced SQL Concepts

• Sorting Data: Results can be arranged in ascending or descending order.
• Aggregate Functions: Perform calculations on multiple records (SUM, COUNT, AVG, etc.).
• Grouping & Filtering: Data can be grouped and filtered based on conditions.
• Nested Queries: Queries within queries help in complex data retrieval.
• Joins: Combine multiple tables to extract meaningful insights:
  • Inner Join: Matches records from both tables.
  • Left Join: Includes all records from one table and matching ones from another.
  • Multiple Joins: Helps in deeper data analysis by linking several tables.