ITI SQL Labs - Complete Solutions
May 25, 2025 · View on GitHub
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📋 Repository Description
ITI DB-SQL Labs Answers by me, featuring:
- Lab Folders: Each lab is organized into its own folder, containing:
- SQL Scripts: Detailed solutions for each lab exercise.
- Backup Files: .bak files for restoring the database state pertinent to each lab.
- Resources: Additional materials to supplement your learning.
📚 Notes & Links helps me revising and remembering:
| Based On Lectures | |
| Helpful Notes |
🚀 Full Power BI Track Materials
Complete collection of BI track materials, projects, and resources.
💡 Database Tip
Pro Tip: Always BACKUP before you ALTER!
| Situation | Backup Type | Risk Level |
|---|---|---|
| Before ALTER TABLE | Full DB | ☠️☠️☠️☠️☠️ |
| Before running DELETE | Transaction Log | ☠️☠️☠️ |
| Before Power BI refresh | .pbix File | ☠️☠️☠️☠️ |
| Before Projects submission | Both .bak and .sql | ☠️☠️☠️☠️☠️ |
🧼 Writing Clean SQL – Make your queries readable
“Good code is its own best documentation.” – Steve McConnell
❌ Before (Spaghetti Code)
select c.customer_id,c.first_name,c.last_name,o.order_id,o.order_date
from customers c join orders o on c.customer_id=o.customer_id
where c.country='germany' and o.quantity>100
✅ After (Clean & Readable)
SELECT
c.customer_id,
c.first_name,
c.last_name,
o.order_id,
o.order_date
FROM customers c
INNER JOIN orders o
ON c.customer_id = o.customer_id
WHERE c.country = 'Germany'
AND o.quantity > 100;