Please note that calling mysqli::commit() will NOT automatically set mysqli::autocommit() back to 'true'.
This means that any queries following mysqli::commit() will be rolled back when your script exits.
(PHP 5, PHP 7, PHP 8)
mysqli::commit -- mysqli_commit — 現在のトランザクションをコミットする
オブジェクト指向型
手続き型
データベース接続の現在のトランザクションをコミットします。
link手続き型のみ: mysqli_connect() あるいは mysqli_init() が返す mysqliオブジェクト。
flags
定数 MYSQLI_TRANS_COR_* のビットマスク。
name
指定した場合は、COMMIT/*name*/ を実行します。
mysqli のエラー報告 (MYSQLI_REPORT_ERROR) が有効になっており、かつ要求された操作が失敗した場合は、警告が発生します。さらに、エラー報告のモードが MYSQLI_REPORT_STRICT に設定されていた場合は、mysqli_sql_exception が代わりにスローされます。
| バージョン | 説明 |
|---|---|
| 8.0.0 |
name は、nullable になりました。
|
注意:
この関数は、トランザクションに 対応していないテーブル型（MyISAM あるいは ISAM など）では 動作しません。
Please note that calling mysqli::commit() will NOT automatically set mysqli::autocommit() back to 'true'.
This means that any queries following mysqli::commit() will be rolled back when your script exits.I never recomend to use the ? with only one value variant like: $var = expression ? $var : other_value or $var = expression ? null : other_value ,and php suport Exception catchin so,use it :)
here my opinion abut lorenzo's post:
<?php
//variants combined
$mysqli->autocommit(FALSE);
try{
$mysqli->query("INSERT INTO myCity (id) VALUES (100)") or throw new Exception('error!');
// or we can use
if( !$mysqli->query("INSERT INTO myCity (id) VALUES (200)"){
throw new Exception('error!');
}
}catch( Exception $e ){
$mysqli->rollback();
}
$mysqli->commit();
?>This is an example to explain the powerful of the rollback and commit functions.
Let's suppose you want to be sure that all queries have to be executed without errors before writing data on the database.
Here's the code:
<?php
$all_query_ok=true; // our control variable
//we make 4 inserts, the last one generates an error
//if at least one query returns an error we change our control variable
$mysqli->query("INSERT INTO myCity (id) VALUES (100)") ? null : $all_query_ok=false;
$mysqli->query("INSERT INTO myCity (id) VALUES (200)") ? null : $all_query_ok=false;
$mysqli->query("INSERT INTO myCity (id) VALUES (300)") ? null : $all_query_ok=false;
$mysqli->query("INSERT INTO myCity (id) VALUES (100)") ? null : $all_query_ok=false; //duplicated PRIMARY KEY VALUE
//now let's test our control variable
$all_query_ok ? $mysqli->commit() : $mysqli->rollback();
$mysqli->close();
?>
hope to be helpful!This is to clarify the Flags parameters and what they mean:
MYSQLI_TRANS_COR_AND_CHAIN:
Appends "AND CHAIN" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_AND_NO_CHAIN:
Appends "AND NO CHAIN" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_RELEASE:
Appends "RELEASE" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_NO_RELEASE:
Appends "NO RELEASE" to mysqli_commit or mysqli_rollback.
To clarify those options:
The AND CHAIN clause causes a new transaction to begin as soon as the current one ends, and the new transaction has the same isolation level as the just-terminated transaction.
The RELEASE clause causes the server to disconnect the current client session after terminating the current transaction.When you have alot of transactions to make, say you are applying inserting items to the database from a loop, it will be better to use the mysqli_commit for this kind of process as it will only hit the database once.
//Wrong way
Example 1:
$con = mysqli_connect("host", "username", "password", "database") or die("Could not establish connection to database");
$users = ["chris", "james", "peter", "mark", "joe", "alice", "bob"]
for($i=0; $i<count($users); $i++){
$user= $users[$i];
$query = mysqli_query($con, "INSERT INTO users (username) VALUES ('$user') ");
}
//Correct Way
Example 2
$con = mysqli_connect("host", "username", "password", "database") or die("Could not establish connection to database");
$users = ["chris", "james", "peter", "mark", "joe", "alice", "bob"]
//Turn off autocommit
mysqli_autocommit($con, FALSE)
//Make some transactions
for($i=0; $i<count($users); $i++){
$user= $users[$i];
$query = mysqli_query($con, "INSERT INTO users (username) VALUES ('$user') ");
}
//Make a one-time hit to the database
mysqli_commit($con)
As with the Example 1, since we had 7 items in the list, this means that their will be a 7 times hit to our database which can really affect performance. But with the Example 2, since we already turned off autocommit this means that the transactions will be queued ontill will explicitly call mysqli_commit($con)