MySQL 多查询 InnoDB

Question

我是 InnoDB 事务的新手。 我正在学习，但我对此有疑问。

<?php
include_once("../../../../../wp-config.php");
global $wpdb;
$cats_table     = $wpdb->prefix . "jb_menu_groups";
$relation       = $wpdb->prefix . "jb_relations";
$mysqli = new mysqli($wpdb->dbhost, $wpdb->dbuser, $wpdb->dbpassword, $wpdb->dbname);
if ($mysqli -> connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli -> connect_error;
    exit();
}

// Turn autocommit off
$mysqli -> autocommit(FALSE);

$mysqli -> query("DELETE FROM $cats_table WHERE id=6");
$mysqli -> query("DELETE FROM $relation WHERE groupid=3");

// Commit transaction
if (!$mysqli -> commit()) {
  echo "Commit transaction failed";

  exit();
}

$mysqli -> rollback();
$mysqli -> close();
?>

如果我创建了一个错误的查询来测试提交和回滚，则代码会成功运行另一个查询。

如何在一个事务中进行多个查询，如果一个查询有错误，请回滚并取消事务？

Answer 1

我个人只使用 PDO 和事务，但这就是它应该如何与 mysqli 一起工作：

// start the transaction
$mysqli->autocommit(false);

$catQuery = $mysqli->query("DELETE FROM $cats_table WHERE id=6");
$relationQuery = $mysqli->query("DELETE FROM $relation WHERE groupid=3");

if ($catQuery && $relationQuery) {
    // in case the db server confirms the correctness of the queries, commit the transaction
    $mysqli->commit();
} else {
    // something went wrong
    $mysqli->rollback();
}

// don't forget to reset the transaction mode again, in case your app isn't ending here
$mysqli->autocommit(true);

请确保不要在事务中包含CREATE, ALTER or DROP语句，因为这会立即提交更改。