SQL – Delete Query

To delete a query in SQL, you can use the DELETE statement. The basic syntax for deleting data from a table is:

DELETE FROM table_name
WHERE some_column = some_value;

For example, if you have a table named “customers” and you want to delete a customer with the ID of 5, you would use the following query:

DELETE FROM customers
WHERE id = 5;

This would delete the customer with an ID of 5 from the “customers” table.

Be careful when using this statement. Deleting data is permanent, and you may not be able to recover it.

Example 2

For example if you want to delete a specific name in a table, you can use the DELETE statement with a WHERE clause. The WHERE clause specifies the exact row or rows to be deleted.

Here’s an example of how to delete a name in a table called “students”:

DELETE FROM students WHERE name = 'Surya Singam';

This query will delete the row where the name is ‘Surya Singam’ in the “students” table.

It’s important to note that once you DELETE a row, it’s gone permanently and it will not be possible to recover it. So, before using DELETE command you should always make sure that you are deleting the right rows and you should also take a backup of the table you are going to delete data from.

Steps to follow before Delete a query in SQL

  1. Backup the data before deleting it.
  2. Verify the data you are going to delete, by selecting the data and checking it in the result set.
  3. Use the “WHERE” clause to specify the exact row or rows to be deleted.
  4. Test the delete query in a development environment before running it in a production environment.
  5. Execute the query and commit the changes.
  6. Verify that the correct data has been deleted by querying the table again.