PHP从Mysql数据库创建变量列表

Question

I've a database that using for 3 languages this way:

id  name    de_de   al_sq
1   title   titel   titulli
2   points  punkte  pike

Now when in php $lang is set to 'al_sq':

$lang = 'al_sq';

I'm trying to generate variables using names of that language, in this case:

$langtitle = 'titulli';
$langpoints = 'pike';

Trying something like:

$sql = "SELECT * FROM `langs`";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
  while($row = $result->fetch_assoc()) {
    $lang{$row["lang"]} = $row[$lang];
  }
}

but something is not good, how to generate these variables?

Answer 1

It seems you are using the database as a key-value store with multiple value fields depending on the language, you could use PDO::FETCH_KEY_PAIR so it returns an array with the name as the key. This way you also avoid loading the data for other languages that you might not need at all:

    $query = "SELECT `name`, :column as value FROM `langs`";
    $statement = $pdo->prepare($query);
    $statement->execute(["column"  => $lang]);
    $data = $statement->fetchAll(\PDO::FETCH_KEY_PAIR);

    // $data becomes an array with the name as the key:
    $langtitle = $data['title'];
    $langpoints = $data['points'];

Make sure, if the user provides the value for $lang , to check that it is a valid column value.

Answer 2

This should be close to what you are wanting based on how your database is presented. Scaling up would be clunky though if there is more the title and points stored.

$lang = 'al_sq';
$sql = "SELECT $lang FROM 'langs'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
 while($row = $result->fetch_assoc()) {
 $langtitle = $row[1];
 $langpoints = $row[2];
 }
}

Answer 3

You have a minor syntax error in your code, which causes an error. What you need to do here is to:

1. Fetch the name and al_sq columns from the database table. This is done by selecting the value of $lang (based on your code). For security reasons, the value of $lang is protected against SQL injection, as you did not specify where the value was coming from.

2. Then you must check if there was any results, and in the case there wasn't any, it will simply terminate the script with an error.

3. Then lastly you must iterate over each row of the returned results, and do a variable variable assignment. This will make $langpoints etc. work (and any other you may add in the future).

Code:

$sql = 'SELECT `name`, `' . $conn->real_escape_string($lang) . '` FROM `langs`';

$result = $conn->query($sql);

if (!$result || !$result->num_rows) {
  echo 'Invalid language selected';
  exit;
}

while ($phrase = $result->fetch_assoc()) {
  ${'lang' . $phrase['name']} = $phrase[$lang];
}

// $langtitle
// $langpoints