在mysqli准备好的语句中使用空值 [英] using nulls in a mysqli prepared statement

问题描述

在mysqli准备好的语句中，NULL变成''(对于字符串)或0(对于整数).我想将其存储为真正的NULL.有什么办法吗?

In a mysqli prepared statement, a NULL gets turned into '' (in the case of a string) or 0 (in the case of an integer). I would like to store it as a true NULL. Is there any way of doing this?

推荐答案

我知道这是一个旧线程，但是可以将真实的NULL值绑定到准备好的语句(请阅读

I know this is an old thread, but it's possible to bind a true NULL value to the prepared statements (read this).

实际上，您可以使用mysqli_bind_parameter将NULL值传递给数据库.只需创建一个变量并将NULL值(请参见手册页)存储到该变量并将其绑定即可.无论如何对我来说很棒.

You can, in fact, use mysqli_bind_parameter to pass a NULL value to the database. simply create a variable and store the NULL value (see the manpage for it) to the variable and bind that. Works great for me anyway.

因此，它必须类似于:

<?php
    $mysqli = new mysqli('localhost', 'my_user', 'my_password', 'world');

    // person is some object you have defined earlier
    $name = $person->name();
    $age = $person->age();
    $nickname = ($person->nickname() != '') ? $person->nickname() : NULL;

    // prepare the statement
    $stmt = $mysqli->prepare("INSERT INTO Name, Age, Nickname VALUES (?, ?, ?)");

    $stmt->bind_param('sis', $name, $age, $nickname);
?>

这应该在数据库中插入一个NULL值.

This should insert a NULL value into the database.

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