MySQL update multiple rows based on id - mysql

Question

In a table in MySQL I'm trying to update a specific field based on the id.
The table has more than 5,000 rows and many fields. One of the fields is "id" and another one that I want to update is called "category" which right now all of them are NULL and I want to update all of them.
my backup mysql file that I want to use has only "id" and "category" which they are like this:
INSERT INTO `products` (`id`, `category`) VALUES
(3, 1),
(4, 1),
(5, 2),
(6, 1),
(7, 5),
(8, 1),
(9, 6),
(10, 1),
...
(5000, 3);
I want to update the "category" field in my table according to the id's in this list and because there is more than 5,000 rows I don't want to change each record manually.
Right now in my table all the "category" fields are NULL and I want to update or give new information to the "category" fields using the file that I have.

Answer 1

The easiest is to use a Temporary table :
CREATE TEMPORARY TABLE temp_products (id int, category int ) ;
Then
INSERT INTO `temp_products` (`id`, `category`) VALUES
(3, 1),
(4, 1),
(5, 2),
(6, 1),
(7, 5),
(8, 1),
(9, 6),
(10, 1),
...
(5000, 3);
Now you just have to use an update with an inner join :
Update products p
INNER JOIN temp_products t_p ON t_p.id = p.id
SET p.category = t_p.category
if you want you can add a where clause :
Update products p
INNER JOIN temp_products t_p ON t_p.id = p.id
SET p.category = t_p.category
WHERE p.category IS NULL

Answer 2

Perhaps the better solution for you can be:
First of all, create temporary table
CREATE TABLE `products_tmp` (
`id` INT NOT NULL,
`category` INT NOT NULL,
PRIMARY KEY (`id`)
);
After that, perform inserts into generated temporary table:
INSERT INTO `products_tmp` (`id`, `category`) VALUES
(3, 1),
(4, 1),
(5, 2),
(6, 1),
(7, 5),
(8, 1),
(9, 6),
(10, 1),
...
(5000, 3);
after this, you can update all fields in your original table:
UPDATE products p
JOIN products_tmp pt ON p.id = pt.id
SET p.category = pt.category;
After this, you can delete temporary table
drop table products_tmp;