So far we’ve learnt how to select data from a database table and how to insert and update data into a database table. Now it’s time to learn how to remove data from a database. Here comes the SQL DELETE statement!
The SQL DELETE command has the following generic SQL syntax:
DELETE FROM Table1
WHERE Some_Column = Some_Value
If you skip the SQL WHERE clause when executing SQL DELETE expression, then all the data in the specified table will be deleted. The following SQL statement will delete all the data from our Customers table and we’ll end up with completely empty table:
If you specify a WHERE clause in your SQL DELETE statement, only the table rows satisfying the WHERE criteria will be deleted:
DELETE FROM Customers
WHERE LastName = 'Smith'
The SQL query above will delete all database rows having LastName 'Smith' and will leave the Customers table in the following state: