MySQL Delete
Maintenance is a very common task that is necessary for
keeping MySQL tables current. From time to time, you may even
need to delete items from your database. Some potential reasons
for deleting a record from MySQL include when: someone deletes a
post from a forum, an employee leaves a company, or you're
trying to destroy your records before the federalies come!
MySQL DELETE Example
The DELETE query is very similar to the
UPDATE Query in the previous lesson.
We need to choose a table, tell MySQL to perform the deletion,
and provide the requirements that a record must have for it to
be deleted.
Say we want to delete the youngest employee from our
previously created table because
he has to go back to school. This is how we do it.
PHP & MySQL Code:
<?php
// Connect to MySQL
// Delete Bobby from the "example" MySQL table
mysql_query("DELETE FROM example WHERE age='15'")
or die(mysql_error());
?>
It is important to note that this query would have deleted
ALL records that had an age of 15. Since Bobby was the only 15
year old this was not a problem.
MySQL DELETE Tips
Before performing a large delete on a database, be sure to
back up the table/database in case your script takes off a
little more than desired. Test your delete queries before even
thinking about using them on your table. As long as you take
caution when using this powerful query you should not run into
any problems.
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