php adodb transaction

1/*
2* Start transaction scope
3*/
4$conn->beginTrans();
5 
6/*
7* Execute some insert or update SQL
8*/
9$ok = $conn->execute($sql);
10 
11if ($ok) {
12   /*
13   * The previous execution succeeded, do some more
14   */ 
15   $ok = $conn->execute($sql2);
16} else {
17   /*
18   * Branch, do some other work, then return
19   */
20}
21 
22if (!$ok) {
23    /*
24    * Test the last insertion, if not successful roll 
25    * back the entire transaction scope
26    */
27    $conn->rollbackTrans();
28} else {
29    /*
30    * Go ahead and commit
31    */ 
32    $conn->commitTrans();
33}