Rolls back an open transaction so that changes you have made to the database are undone as though they were never made. Returns TRUE if everything went well, FALSE if unsuccessful. Trying to roll back a transaction that already has been committed or rolled back is considered to be an error and therefore returns FALSE.
The behaviour of this function varies slightly depending on the optional parameter trans . The 3 possible cases are:
Available in PHP 3 since 3.0.7, PHP 4 since 4.0RC1
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing (Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch). This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/). The authors of this book have elected not to choose any options under the OPL. This online book was obtained from http://www.fooassociates.com/phpfer/ and is designed to provide information about the PHP programming language, focusing on PHP version 4.0.4 for the most part. The information is provided on an as-is basis, and no warranty or fitness is implied. All persons and entities shall have neither liability nor responsibility to any person or entity with respect to any loss or damage arising from the information contained in this book.