What about Transactions? They have the ROLLBACK-Feature.

@see https://dev.mysql.com/doc/refman/5.0/en/commit.html

For example:

START TRANSACTION;SELECT * FROM nicetable WHERE somthing=1;UPDATE nicetable SET nicefield='VALUE' WHERE somthing=1;SELECT * FROM nicetable WHERE somthing=1; #checkCOMMIT;# or if you want to reset changes ROLLBACK;SELECT * FROM nicetable WHERE somthing=1; #should be the old value

Answer on question from @rickozoe below:

In general these lines will not be executed as once. In PHP f.e. you would write something like that (perhaps a little bit cleaner, but wanted to answer quick ;-) ):

$MysqlConnection->query('START TRANSACTION;');$erg = $MysqlConnection->query('UPDATE MyGuests SET lastname='Doe' WHERE id=2;');if($erg)    $MysqlConnection->query('COMMIT;');else    $MysqlConnection->query('ROLLBACK;');

Another way would be to use MySQL Variables (see https://dev.mysql.com/doc/refman/5.7/en/user-variables.htmlandhttps://stackoverflow.com/a/18499823/1416909):

# do some stuff that should be conditionally rollbacked later onSET @v1 := UPDATE MyGuests SET lastname='Doe' WHERE id=2;IF(v1 < 1) THEN    ROLLBACK;ELSE    COMMIT;END IF;

But I would suggest to use the language wrappers available in your favorite programming language.

In addition to using a transaction as Imad has said (which should be mandatory anyway) you can also do a sanity check which rows are affected by running a select using the same WHERE clause as the UPDATE.

So if you UPDATE is

UPDATE foo  SET bar = 42WHERE col1 = 1  AND col2 = 'foobar';

The following will show you which rows will be updated:

SELECT *FROM fooWHERE col1 = 1  AND col2 = 'foobar';

Autocommit OFF ...

MySQL

set autocommit=0;

It sets the autommit off for the current session.

You execute your statement, see what it has changed, and then rollback if it's wrong or commit if it's what you expected !

EDIT: The benefit of using transactions instead of running select query is that you can check the resulting set easierly.