我可以在预处理语句中参数化表名吗？

我已经多次使用 mysqli _ stmt _ bind _ param 函数。但是，如果我将要防止 SQL 注入的变量分开，就会遇到错误。

下面是一些代码示例:

function insertRow( $db, $mysqli, $new_table, $Partner, $Merchant, $ips, $score, $category, $overall, $protocol )
{
$statement = $mysqli->prepare("INSERT INTO " .$new_table . " VALUES (?,?,?,?,?,?,?);");
mysqli_stmt_bind_param( $statment, 'sssisss', $Partner, $Merchant, $ips, $score, $category, $overall, $protocol );
$statement->execute();
}

是否有可能以某种方式将 .$new_table.连接替换为另一个问号语句，创建另一个绑定参数语句，或者添加到现有语句上以防止 SQL 注入？

比如这个或者其他形式的:

function insertRow( $db, $mysqli, $new_table, $Partner, $Merchant, $ips, $score, $category, $overall, $protocol )
{
$statement = $mysqli->prepare("INSERT INTO (?) VALUES (?,?,?,?,?,?,?);");
mysqli_stmt_bind_param( $statment, 'ssssisss', $new_table, $Partner, $Merchant, $ips, $score, $category, $overall, $protocol );
$statement->execute();
}

40077

小开

最佳答案

Short answer to your question is "no".

In the strictest sense, at the database level, prepared statements only allow parameters to be bound for "values" bits of the SQL statement.

One way of thinking of this is "things that can be substituted at runtime execution of the statement without altering its meaning". The table name(s) is not one of those runtime values, as it determines the validity of the SQL statement itself (ie, what column names are valid) and changing it at execution time would potentially alter whether the SQL statement was valid.

At a slightly higher level, even in database interfaces that emulate prepared statement parameter substitution rather than actually send prepared statements to the database, such as PDO, which could conceivably allow you to use a placeholder anywhere (since the placeholder gets replaced before being sent to the database in those systems), the value of the table placeholder would be a string, and enclosed as such within the SQL sent to the database, so SELECT * FROM ? with mytable as the param would actually end up sending SELECT * FROM 'mytable' to the database, which is invalid SQL.

Your best bet is just to continue with

SELECT * FROM {$mytable}

but you absolutely should have a white-list of tables that you check against first if that $mytable is coming from user input.