mysqli - begin_transaction() method undefined in php 5.6.2 -

mysqli - begin_transaction() method undefined in php 5.6.2 -

i go on receive error when using method begin_transaction() in php 5.6.2...the method supposed work of php 5.5. i'm not sure i'm missing...any ideas? config in php?

here's statement: $mysqli->begin_transaction();

here's error: fatal error: phone call undefined method file::begin_transaction()

php mysqli