SQL Transactions Interactive Demo
Master SQL Transactions with Fullstackgada’s fun approach! 🗄️
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🔄 SQL Transactions Explorer
Transactions: All or nothing! Update stock, add order, process payment—either everything succeeds or nothing does.
BEGIN
(Start Transaction)
(Start Transaction)
Stock -1
(Reduce Stock)
(Reduce Stock)
Order Added
(Insert Order)
(Insert Order)
Payment
(Process Payment)
(Process Payment)
Commit or Rollback?
🏠 Wedding Ceremony Analogy
Transaction = Wedding Ceremony!
🪔
Three rituals: Haldi, Vows, Ring... If one fails, the wedding is canceled (Rollback)!
🎉
All rituals complete? Commit – Wedding confirmed!
😨
Power outage in the middle? Rollback – Everything resets, as if nothing happened.
💡 Transaction Properties (ACID)
A
Atomicity: All or nothingC
Consistency: Data always follows rulesI
Isolation: Transactions are independentD
Durability: Committed data is safe🔢 Example: Orders and Stock Tables
🛒 Orders Table
| OrderID | Product | Qty | Status |
|---|
📦 Stock Table
| Product | StockLeft |
|---|
💻 SQL Transaction Example
BEGIN;
/* Step 1: Reduce stock */
UPDATE Stock SET count = count - 1 WHERE product='Soap';
/* Step 2: Insert order */
INSERT INTO Orders(product, qty, status) VALUES ('Soap', 1, 'Pending');
/* Step 3: Payment */
-- Imagine payment step here
/* All good */
COMMIT;
/* If an error occurs */
ROLLBACK;
Only COMMIT saves data! If an error occurs, ROLLBACK reverts everything.