Normalization

```sql
CREATE TABLE products (
	product_id INT(11) PRIMARY KEY AUTO_INCREMENT,
	product_desc  VARCHAR(250) NOT NULL UNIQUE,
	imagesrc VARCHAR(250)    
);

SELECT 
CONCAT('INSERT INTO products (product_id, product_desc) VALUES (', @rownum, ',\'', product_id, '\');') AS sql_stmt,
CONCAT('UPDATE local set product_id = ', @rownum, ' WHERE product_id = \'', product_id, '\';') AS sql_stmt,
product_id,
@rownum := @rownum + 1
FROM 
(
SELECT 
	DISTINCT product_id
FROM
  LOCAL
WHERE product_id IS NOT NULL
  AND product_id <> ''
) AS tbl
,(SELECT @rownum := 1) r;


ALTER TABLE `local` CHANGE `product_id` `product_id` INT(11) NOT NULL;
```