UPDATE and DELETE

It's time to get back to writing queries and consider two more statements.

You already know how to clear a table, add a column, insert data, etc. But for proper interaction with the database, we need to understand how to update and delete individual rows.

For this, there are two statements and types of queries: the UPDATE and the DELETE queries.

Let's look at an example with the medications table:

Let's imagine we need to update the price for a specific type of medication. For example, currently, there's a 50% discount on ibuprofen, and we need to change the price for this product.

Our UPDATE query will look like this:

UPDATE medications

SET price = 4

WHERE id = 2;

SELECT *

FROM medications

ORDER BY id;


              1234567
            
UPDATE medications
SET price = 4
WHERE id = 2;

SELECT * 
FROM medications
ORDER BY id;


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UPDATE table_name
SET column_name = значення
WHERE якась_умова;

DELETE

Операція команди DELETE майже ідентична за принципом. Однак тут ми не використовуємо ключове слово SET, адже ми нічого не змінюємо; ми просто видаляємо рядки.

Синтаксис для видалення виглядатиме так:

Але я нагадаю вам, що видалення рядків слід проводити обережно, адже ви не зможете легко їх відновити.

Примітка

Якщо ви не включите умову WHERE, дані будуть оновлені або видалені для усіх рядків.

Переходимо до практики!


sql
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DELETE FROM table_name
WHERE some_condition;

But I'll remind you that deleting rows should be done with caution, as you won't be able to simply recover them.

Note

If you don't include a WHERE condition, the data will be updated or deleted for all rows.

Завдання

Swipe to start coding

In the pharmaceutical market, there's inflation!

The supplier company informed us that we must urgently establish a minimum price of 10 units for the product. So your task will be to update the table so that the price, which was previously less than 10, becomes 10. You can do this using the UPDATE statement.

Brief Instructions

Use the UPDATE statement to modify the medications table.
Use SET to assign a new value of 10 to the price column.
Use the WHERE clause with the condition price < 10 so that the update only applies to rows meeting this requirement.