Chapter 13: SQL Basics
13.5 Deleting Data from Tables
In some situations, such as when a user wants to remove outdated or irrelevant information from a database, it is necessary to delete data from tables. The SQL DELETE statement is used for this purpose.
When using the DELETE statement, it is important to specify the table from which data should be removed and the conditions that must be met for the data to be deleted. Additionally, it is possible to use the WHERE keyword to further refine the deletion criteria and ensure that only the desired data is removed.
It is important to exercise caution when using the DELETE statement to ensure that important data is not inadvertently removed.
Example:
For instance, suppose we no longer want to keep track of "The Great Gatsby" in our 'Books' table. We could remove it like so:
DELETE FROM Books
WHERE Title = 'The Great Gatsby';As with the UPDATE statement, you must be careful when using DELETE. If you leave out the WHERE clause, DELETE will remove all rows from the table!
13.5 Deleting Data from Tables
In some situations, such as when a user wants to remove outdated or irrelevant information from a database, it is necessary to delete data from tables. The SQL DELETE statement is used for this purpose.
When using the DELETE statement, it is important to specify the table from which data should be removed and the conditions that must be met for the data to be deleted. Additionally, it is possible to use the WHERE keyword to further refine the deletion criteria and ensure that only the desired data is removed.
It is important to exercise caution when using the DELETE statement to ensure that important data is not inadvertently removed.
Example:
For instance, suppose we no longer want to keep track of "The Great Gatsby" in our 'Books' table. We could remove it like so:
DELETE FROM Books
WHERE Title = 'The Great Gatsby';As with the UPDATE statement, you must be careful when using DELETE. If you leave out the WHERE clause, DELETE will remove all rows from the table!
13.5 Deleting Data from Tables
In some situations, such as when a user wants to remove outdated or irrelevant information from a database, it is necessary to delete data from tables. The SQL DELETE statement is used for this purpose.
When using the DELETE statement, it is important to specify the table from which data should be removed and the conditions that must be met for the data to be deleted. Additionally, it is possible to use the WHERE keyword to further refine the deletion criteria and ensure that only the desired data is removed.
It is important to exercise caution when using the DELETE statement to ensure that important data is not inadvertently removed.
Example:
For instance, suppose we no longer want to keep track of "The Great Gatsby" in our 'Books' table. We could remove it like so:
DELETE FROM Books
WHERE Title = 'The Great Gatsby';As with the UPDATE statement, you must be careful when using DELETE. If you leave out the WHERE clause, DELETE will remove all rows from the table!
13.5 Deleting Data from Tables
In some situations, such as when a user wants to remove outdated or irrelevant information from a database, it is necessary to delete data from tables. The SQL DELETE statement is used for this purpose.
When using the DELETE statement, it is important to specify the table from which data should be removed and the conditions that must be met for the data to be deleted. Additionally, it is possible to use the WHERE keyword to further refine the deletion criteria and ensure that only the desired data is removed.
It is important to exercise caution when using the DELETE statement to ensure that important data is not inadvertently removed.
Example:
For instance, suppose we no longer want to keep track of "The Great Gatsby" in our 'Books' table. We could remove it like so:
DELETE FROM Books
WHERE Title = 'The Great Gatsby';As with the UPDATE statement, you must be careful when using DELETE. If you leave out the WHERE clause, DELETE will remove all rows from the table!