为什么我不能运行两个mysqli查询?第二个失败 [英] Why can't I run two mysqli queries? The second one fails
问题描述
是否可以像这样有两个mysqli查询?
Is it possible to have two mysqli queries like so?
mysqli_query($dblink, "INSERT INTO images (project_id, user_id, image_name, date_created, link_to_file, link_to_thumbnail, given_name) VALUES ('$project_id', '$user_id', '$image_name', '$date_created', '$link_to_file', '$thumbnail', '$ImageName')");
mysqli_query($dblink, "INSERT INTO images_history (project_id, user_id, image_name, date_created, link_to_file, link_to_thumbnail, given_name, day, month, year) VALUES ('$project_id', '$user_id', '$image_name', '$date_created', '$link_to_file', '$thumbnail', '$ImageName', '$day', '$month', '$year')");
基本上,我想更新数据库中的两个表.有更好的方法吗?
Basically I want to update two tables in my DB. Is there a better way to do this?
推荐答案
可以使用 mysqli_multi_query().
示例:
<?php
$mysqli = new mysqli($host, $user, $password, $database);
// create string of queries separated by ;
$query = "INSERT INTO images (project_id, user_id, image_name, date_created, link_to_file, link_to_thumbnail, given_name) VALUES ('$project_id', '$user_id', '$image_name', '$date_created', '$link_to_file', '$thumbnail', '$ImageName');";
$query .= "INSERT INTO images_history (project_id, user_id, image_name, date_created, link_to_file, link_to_thumbnail, given_name, day, month, year) VALUES ('$project_id', '$user_id', '$image_name', '$date_created', '$link_to_file', '$thumbnail', '$ImageName', '$day', '$month', '$year');";
// execute query - $result is false if the first query failed
$result = mysqli_multi_query($mysqli, $query);
if ($result) {
do {
// grab the result of the next query
if (($result = mysqli_store_result($mysqli)) === false && mysqli_error($mysqli) != '') {
echo "Query failed: " . mysqli_error($mysqli);
}
} while (mysqli_more_results($mysqli) && mysqli_next_result($mysqli)); // while there are more results
} else {
echo "First query failed..." . mysqli_error($mysqli);
}
关键是要在单个调用中执行多个查询,必须 使用mysqli_multi_query
.出于安全原因,mysqli_query
不会执行多个查询来防止SQL注入.
The key is that you must use mysqli_multi_query
if you want to execute more than one query in a single call. For security reasons, mysqli_query
will not execute multiple queries to prevent SQL injections.
还请记住mysqli_store_result
的行为.如果查询没有结果集(INSERT
查询没有结果集),它将返回FALSE
.因此,您还必须检查mysqli_error
以查看它返回的空字符串表示INSERT
成功.
Also keep in mind the behavior of mysqli_store_result
. It returns FALSE
if the query has no result set (which INSERT
queries do not) so you must also check mysqli_error
to see that it returns an empty string meaning the INSERT
was successful.
请参阅:
mysqli_multi_query
mysqli_more_results
mysqli_next_result
mysqli_store_result
See:
mysqli_multi_query
mysqli_more_results
mysqli_next_result
mysqli_store_result
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