Lesson 21: Delete data from database
In the two previous lessons, you have learned to insert and retrieve data from a database. In this lesson, we'll look at how to delete records in the database, which is considerably easier than inserting data.
Delete data using SQL
The syntax for an SQL statement that deletes records is:
DELETE FROM TableName WHERE condition
Example: Delete a record
When deleting a record, you can use the unique AutoNumber field in the database. In our database, it is the column named id. Using this unique identifier ensures that you only delete one record. In the next example, we delete the record where id has the value 24:
<html> <head> <title>Delete data in the database</title> </head> <body> <?php // Connect to database server mysql_connect("mysql.myhost.com", "user", "sesame") or die (mysql_error ()); // Select database mysql_select_db("mydatabase") or die(mysql_error()); // The SQL statement that deletes the record $strSQL = "DELETE FROM people WHERE id = 24"; mysql_query($strSQL); // Close the database connection mysql_close(); ?> <h1>Record is deleted!</h1> </body> </html>
Remember that there is no "Recycle Bin" when working with databases and PHP. Once you have deleted a record, it is gone and cannot be restored.