使用另一个文件中的变量设置数据库连接 [英] Setting up a db connection using variables from another file

问题描述

我正在尝试为 mysqli_connect 语句 $dbc 设置数据库连接.我在我的脚本中使用了以下内容:

I am attempting to set up a db connection for a mysqli_connect statement $dbc. I had it working in my script with the following:

DEFINE ('DB_USER','myName';
DEFINE ('DB_PASSWORD','somePass123';
DEFINE ('DB_HOST','localhost';
DEFINE ('DB_NAME','sitename';


// make the db connection
    $dbc = @mysqli_connect(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME)
    OR die ('Could not connect to mysql: ' . mysqli_connect_error());

然后我在 SO 上发布了一个关于安全性和最佳实践的问题，并被告知如果连接变量(密码、主机、dbname、用户)存在于单独的数据库配置文件中的其他地方，我应该调用连接变量从那里开始.

I then posted a question on SO about security and best practice and was advised that if the connection variables (password, host, dbname, user) exist elsewhere in a separate database configuration file, that I should call the variables for the connection from there.

这是来自 config/database/php 文件的相关片段

Here is the relevant snippet from the file in config/database/php

$config['default'] = array(
    'benchmark' => TRUE,
    'persistent' => FALSE,
    'connection' => array(
        'type' => 'mysqli',
        'user' => 'myName',
        'pass' => 'somepass123',
        'host' => 'localhost',
        'port' => FALSE,
        'socket' => FALSE,
        'database' => 'sitename',
    ),
    'character_set' => 'utf8',
    'table_prefix' => '',
    'object' => TRUE,
    'cache' => FALSE,
    'escape' => TRUE
);

于是我尝试了这个:

DEFINE ('DB_USER','$config['default']['connection']['user'])';
DEFINE ('DB_PASSWORD',$config['default']['connection']['pass']);
DEFINE ('DB_HOST',$config['default']['connection']['host']);
DEFINE ('DB_NAME',$config['default']['connection']['database']);


// make the db connection
    $dbc = @mysqli_connect(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME)
    OR die ('Could not connect to mysql: ' . mysqli_connect_error());

当我尝试加载页面时产生以下错误:未定义变量:配置"

Which produced the following error when I tried to load the page: "Undefined variable: config"

然后我尝试了这个:

 $dbc = @mysqli_connect(
    $config['default']['connection']['host'],
    $config['default']['connection']['user'],
    $config['default']['connection']['pass'],
    $config['default']['connection']['database'])

    OR die ('Could not connect to mysql: ' . mysqli_connect_error());

// Set the encoding
mysqli_set_charset($dbc, 'utf8');

// set the query variable
$query = "SELECT MAX(rating_date) 
          AS last_date
          FROM rating
          WHERE incident_id = $incident_id;";

//connect and run the query
$result = mysqli_query($dbc, $query);

 echo $result->fetch_object()->last_date;

?>

然后产生以下错误:致命错误:在...中的非对象上调用成员函数 fetch_object()"

Which then produced the following error: "Fatal error: Call to a member function fetch_object() on a non-object in..."

我不是 100% 确定这告诉我什么.昨天我了解到不能直接在 php 中回显 SQL 查询，因为它是一个对象，所以我剪切 n 粘贴了echo $result->fetch_object()->last_date;"部分.哪个有效.

I'm not 100% sure what this is telling me. Yesterday I learned that one cannot echo a SQL query in php directly because it's an object so I cut n pasted the part "echo $result->fetch_object()->last_date;" which worked.

现在我似乎试图从配置中提取变量，而不仅仅是在函数中定义它们，我可能由于范围问题而无法连接?

It seems that now that I am trying to draw upon the variables from config, rather than just define them in the function, I am unable to connect perhaps due to a scope issue?

具有 $dbc 连接的文件位于文件夹 themes/myname/views/reports/detail.php

The file with the $dbc connection is in a folder themes/myname/views/reports/detail.php

包含数据库配置细节数组的文件在 application/config/database.php

The file with the database configuration details array is in application/config/database.php

好像是变量作用域的问题?

It looks like an issue of variable scope?

制作 $dbc 变量的最佳实践是什么?当 database.php 存在于与我调用它的文件不同的目录中时，如何从它调用变量?我必须包含()整个文件吗?

What would be the best practice here in making my $dbc variable? How do I call the variables from database.php when it exists in a different directory than the file where I'm calling it? Must I include() the whole file?

推荐答案

sane 怎么样:

$dbc = @mysqli_connect(
  $config['default']['connection']['host'],
  $config['default']['connection']['user'],
  $config['default']['connection']['pass'],
  $config['default']['connection']['database'])
OR die ('Could not connect to mysql: ' . mysqli_connect_error());

使用 define() 没有任何好处，你只是想避免将带有用户名和密码的原始字符串放入 mysqli_connect()调用以防发生错误并且该行在错误消息/堆栈跟踪中发送到客户端.

You don't gain anything by using define(), you're only trying to avoid putting the raw strings with your username and password into the mysqli_connect() call in case an error occurs and that line gets sent to the client in an error message/stack trace.

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