Removing Data from All Rows in a Table1:27 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>;
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.
[MUSIC] 0:00 Remember the four CRUD operations, create, read, update, and delete. 0:04 We know the first three keywords too. 0:10 Insert to create, select to read, and update to update. 0:12 Just like update, delete's keyword is the same as the action. 0:16 Delete. 0:19 To write a delete statement, you'd write something like this. 0:20 DELETE FROM table name. 0:23 The delete keyword removes rows from a table. 0:26 It doesn't just empty the rows' values, it removes the rows altogether. 0:30 Let's delete all the data from a table. 0:35 Let’s imagine we’ve had the sad news that our library was closing down. 0:38 We’ve sold all the books in our library, and 0:43 we need to get rid of all the personal data in our library. 0:45 Let’s use the DELETE FROM statement to remove all data from the books table. 0:49 When we view the books table now, there are no rows remaining. 0:58 Now how about wiping out all of the sensitive 1:02 information from the patrons table? 1:05 We can just modify the delete from book state to say delete from patrons. 1:08 Simple. 1:16 When we execute this now, all of the patron information has been removed. 1:17 It's important to note, you can't undo this. 1:22 Without a backup of your data, you can't restore it. 1:24
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