Chapter 1 (English)

8. Difference Between Schema and Instance

Schema:-

·  Aschema is the design or blueprint of a database.

• It tells how the data is organized — like table names, column names, data types, and relationships.

🟢 Example:
In a school database, a table called Students might have:

• Roll_No (number)
• Name (text)
• Class (text)
• Marks (number)

This structure is the schema — it’s like a plan or layout.

Instance:-

·  Aninstance is the actual data stored in the database at a particular moment.

• It keeps changing as we add, delete, or update data.

🟢 Example:
In the Students table, these are instances:

🆚 Difference Between Schema and Instance