← DBMS & SQL learning pathDBMS & SQL · Module 10 of 10
Indexes, views and real-world SQL
Speed up queries with indexes, simplify them with views, and keep data secure.
📖 Key ideas
- An index speeds up searches on a column, like a book index.
- Indexes speed reads but slow writes and use space.
- A view is a saved query you can select from like a table.
- Stored procedures and triggers run logic inside the database.
- Use parameterised queries in apps to prevent SQL injection; grant least privilege.
💡 Real-life example: An index is the index page at the back of a textbook: you jump straight to "Normalization, page 87".
IndexStructure that speeds up lookups
ViewSaved query used like a table
TriggerCode that runs on insert/update/delete
SQL injectionAttack using unsafe query building