Page 61 - Modular_V2.0_SQL_Flipbook

WHERE PRODUCTS.Product_id = SALES.Product_id;

SELECT * FROM PRODUCT_SALES;
Output:
+--------------+-------+----------+----------+
| Product_name | Price | Quantity | Discount |
+--------------+-------+----------+----------+
| Laptop | 50000 | 5 | 500 |
+--------------+-------+----------+----------+
| Smartphone | 15000 | 10 | 1000 |
+--------------+-------+----------+----------+
| Headphones | 2500 | 15 | 200 |
+--------------+-------+----------+----------+
| Keyboard | 1500 | 8 | 100 |
+--------------+-------+----------+----------+
Updating Views

Rules to be kept in mind before Updating Views are as follows:

A view must be based on only one table to be updated.
You cannot update a view that uses JOIN, GROUP BY, DISTINCT, or UNION.

Only columns shown in the view can be updated.
You must include all NOT NULL columns from the base table.
You need the correct permissions to update a view.

Views containing calculations or aggregate functions cannot be updated.

Updates must follow all rules of the original table structure.
Views can be updated using the following ways:

1. When data needs to be updated in a view, the following syntax is used:

UPDATE view_name
SET column_name = value
WHERE condition;

Example using tables: PRODUCTS and SALES

UPDATE PRODUCT_SALES
SET Discount = Discount + 100
WHERE Discount = 200;

SELECT * FROM PRODUCT_SALES;
Output:
+--------------+----------+----------+----------+
| Product_name | Price | Quantity | Discount |
+--------------+----------+----------+----------+
| Laptop | 50000 | 5 | 500 |
+--------------+----------+----------+----------+
| Smartphone | 15000 | 10 | 1000 |
+--------------+----------+----------+----------+
| Headphones | 2500 | 15 | 300 |
+--------------+----------+----------+----------+
| Keyboard | 1500 | 8 | 100 |
+--------------+----------+----------+----------+

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Advanced Features of MySQL