Removing Data from All Rows in a Table

1:27 with Andrew Chalkley

In this video we'll see how to delete all data from a table.

To delete all rows from a table:

DELETE FROM <table>;

Examples:

DELETE FROM logs;
DELETE FROM users;
DELETE FROM products;

See all of the SQL used in Modifying Data With SQL in the Modifying Data With SQL Cheatsheet.

0:00
[MUSIC]
0:04
Remember the four CRUD operations, create, read, update, and delete.
0:10
We know the first three keywords too.
0:12
Insert to create, select to read, and update to update.
0:16
Just like update, delete's keyword is the same as the action.
0:19
Delete.
0:20
To write a delete statement, you'd write something like this.
0:23
DELETE FROM table name.
0:26
The delete keyword removes rows from a table.
0:30
It doesn't just empty the rows' values, it removes the rows altogether.
0:35
Let's delete all the data from a table.
0:38
Let’s imagine we’ve had the sad news that our library was closing down.
0:43
We’ve sold all the books in our library, and
0:45
we need to get rid of all the personal data in our library.
0:49
Let’s use the DELETE FROM statement to remove all data from the books table.
0:58
When we view the books table now, there are no rows remaining.
1:02
Now how about wiping out all of the sensitive
1:05
information from the patrons table?
1:08
We can just modify the delete from book state to say delete from patrons.
1:16
Simple.
1:17
When we execute this now, all of the patron information has been removed.
1:22
It's important to note, you can't undo this.
1:24
Without a backup of your data, you can't restore it.

You need to sign up for Treehouse in order to download course files.

Sign in