Php - Mysqli : Transactions

[shashib]

I have many select insert update query , i have written transaction query but want to know if its safe or some need to be corrected.

 

Also if all is ok i should get successful "Transaction completed successfully!" , but if something get wrong then error message showed be seen and ROLLBACK should be done , but its NOT .... not rollback is done

 

Below is what I have tried. Please let me know if something is wrong:

function autocommitfalse(){global $db;return mysqli_autocommit($db, FALSE);}function autocommittrue(){global $db;return mysqli_autocommit($db, TRUE);}function commitquery(){global $db;return mysqli_commit($db);}function rollbackedquery(){global $db;return mysqli_rollback($db);}

===============================================================================

try {global $db;autocommitfalse();-----------------$SQLSELECT = "SELECT * FROM BC ";$result_as = mysqli_query($db,$SQLSELECT);$rsfetch = mysql_fetch_array($result_as);if(!$result_as ){throw new Exception('Wrong SQL SELECT: ' . $SQLSELECT. ' Error: '.db_error_msg($db) . db_error_no());}-----------------$sqla ="INSERT INTO A (sd) VALUES ('df') where id=".$rsfetch['dh'];$result_a = mysqli_query($db,$sqla);if(!$result_a){throw new Exception('Wrong SQL SELECT: ' . $result_a. ' Error: '.db_error_msg($db) . db_error_no());}-----------------$sqlb ="INSERT INTO B (sdds) VALUES ('trtrt') where id=".$rsfetch['dh'];$result_b =mysqli_query($db,$sqlb);if(!$result_{throw new Exception('Wrong SQL SELECT: ' . $result_a. ' Error: '.db_error_msg($db) . db_error_no());}-----------------$a = mysqli_insert_id($db);-----------------$sqlCb ="UPDATE CB SET A ='NM' where id=".$a ;$result_Cb = mysqli_query($db,$sqlCb);if($result_Cb === false || mysqli_affected_rows($db) == 0 ){throw new Exception('Wrong SQL SELECT: ' . $result_a. ' Error: '.db_error_msg($db) . db_error_no());}-----------------commitquery();echo 'Transaction completed successfully!';} catch (Exception $e) {echo"<br >";echo "<table align=center><tr><td>";echo $e->getMessage();echo "</td></tr></table>";echo"<br >";echo display_error(_("Transaction failed: transaction rolled back"));rollbackedquery();}autocommittrue();

Please let me know its correct or not , if need to correct then what , as still not rollbacked with above code..

Edited February 14, 2014 by shashib

[justsomeguy]

I don't see any obvious problems, it looks like it should work.