Mysql transaction processing application instance of pdo in php. This article will introduce you to mysql transaction processing application instances of pdo in php. For more information, see. Php + mysql transaction processing steps: 1. disable automatic submission 2. start this article to introduce you to mysql transaction processing application instances of pdo in php. For more information, see.
Several steps for php + mysql transaction processing:
1. disable automatic submission
2. start transaction processing
3. if an exception exists, the system automatically throws the exception prompt and rolls back.
4. enable automatic submission
Note: Only the InnoDB driver in mysql supports transaction processing. by default, the MyIsAM driver does not.
The following is the instance code:
| The code is as follows: |
|
Try {
$ Pdo = new pdo ("mysql: host = localhost; dbname = mydb", "root", "root", array (PDO: ATTR_AUTOCOMMIT => 0 )); // disable automatic submission.
// $ Pdo-> setAttribute (PDO: ATTR_AUTOCOMMIT, 0); // This is to disable automatic submission by setting the attribute method, which is the same as the above function
$ Pdo-> setAttribute (PDO: ATTR_ERRMODE, PDO: ERRMODE_EXCEPTION); // enable exception handling
} Catch (PDOException $ e ){
Echo "database connection failed:". $ e-> getMessage ();
Exit;
}
/*
* Transaction processing
*
* John bought a 2000 yuan computer from Li Si.
* Deduct RMB 2000 from Michael Jacob's account
* Add RMB 2000 to the account Li Si
* Reduce a computer from the commodity table
* MyIsAM InnoDB
*/
Try {
$ Pdo-> beginTransaction (); // start transaction processing
$ Price = 500;
$ SQL = "update zhanghao set price = price-{$ price} where id = 1 ";
$ Affected_rows = $ pdo-> exec ($ SQL );
If (! $ Affected_rows)
Throw new PDOException ("Michael Jacob transfer failed"); // The error throws an exception.
$ SQL = "update zhanghao set price = price + {$ price} where id = 3 ";
$ Affected_rows = $ pdo-> exec ($ SQL );
If (! $ Affected_rows)
Throw new PDOException ("failed to transfer to Li Si ");
Echo "transaction successful! ";
$ Pdo-> commit (); // submit if the transaction is successful
} Catch (PDOException $ e ){
Echo $ e-> getMessage ();
$ Pdo-> rollback ();
}
$ Pdo-> setAttribute (PDO: ATTR_AUTOCOMMIT, 1); // automatic submission. if not, the transfer is unsuccessful.
// Set the error report mode ERRMODE_SILENT ERRMODE_WARNING |
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