What Is a Database?
Every app you use — Instagram, Spotify, your school's grading system — stores data in a database. A database is an organized collection of data. A relational database stores data in tables with rows and columns, and uses SQL to retrieve and manipulate that data.
Key Concepts
Tables, Rows, and Columns
A database table is like a spreadsheet. Each column is a field (username, age, score). Each row is one record. A table called 'students' might have columns: id, name, grade, email. Every row is one student.
Why Not Just Use Files?
Files work for small data. Databases shine when you have millions of records, multiple users accessing data at once, need to search/filter/sort quickly, or need to link related data. A database handles all of this efficiently.
Relational Databases
In a relational database, tables relate to each other. A 'courses' table and a 'students' table can be linked — each student enrollment record knows which student and which course it belongs to. This eliminates duplicate data.
🆕 Database Explorer
Explore a sample school database. Click a table to see its structure.
✅ Check Your Understanding
1. What is a database table?
2. Why are relational databases better than files for large data?
3. What does 'relational' mean in relational database?