Using transaction instances in PHP

<?php
$handler =mysql_connect ("localhost", "root", "password");
mysql_select_db ("task");
mysql_query ("Set autocommit=0");//set to not commit automatically because MySQL executes
the mysql_query ("Begin") immediately by default;//starts the transaction definition
if (!mysql_query ( "INSERT into trans (ID) VALUES (' 2 ')"))
{
mysql_query ("Roolback");//To determine if
(!mysql_query () rollback} if execution fails INSERT into trans (ID) VALUES (' 4 '))
} {mysql_query ("roolback");//Judgment execution failed rollback
}
mysql_query (" COMMIT ")//Executive Affairs
Mysql_close ($handler);
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