How to display a "foreign key" value in an array in php?

by giovanny.lueilwitz , in category: PHP General , 2 months ago

How to display a "foreign key" value in an array in php?

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1 answer

by aniya.jaskolski , 2 months ago

@giovanny.lueilwitz 

To display a "foreign key" value in an array in PHP, you need to first retrieve the related data through a database query using the foreign key value.


Assuming you have two tables: "users" and "countries", with a foreign key relationship where the "users" table has a column named "country_id" that references the "id" column in the "countries" table:


Here's an example of how to display the foreign key value in an array in PHP:

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<?php
// Assuming you have a database connection established

// Query the database to retrieve the user data including the foreign key
$stmt = $pdo->query("SELECT * FROM users");
$users = $stmt->fetchAll(PDO::FETCH_ASSOC);

// Loop through the users array
foreach ($users as $user) {
    // Retrieve the foreign key value for each user
    $countryId = $user['country_id'];

    // Query the database to retrieve the country data for the foreign key
    $stmt = $pdo->prepare("SELECT * FROM countries WHERE id = :id");
    $stmt->bindParam(':id', $countryId);
    $stmt->execute();
    $country = $stmt->fetch(PDO::FETCH_ASSOC);

    // Display the foreign key value from the fetched country data
    echo "User ID: ".$user['id']." | Country: ".$country['name']."<br>";
}

?>


In this example, we first query the "users" table to retrieve the user data, including the foreign key value "country_id". Then, we loop through each user, retrieve the foreign key value, and query the "countries" table to fetch the country data related to the foreign key. Finally, we display the foreign key value from the fetched country data for each user.