如何使用MySQLI vs MySQL显示数据库中特定表行列的数据

Question

I am still really new to MySQL and even newer to MySQLI. I am trying to update my website with MySQLI and I can't seem to fix this last issue.

My website is a single page site with 50 categories on the page. Each category has a category title. I have a table in the database with all 50 category titles and id's. I was using MySQL/PHP to display each category title at the top of each category by choosing the row and column specifically. Here is my code..

The Query:

$query_meta = mysql_query("SELECT * FROM `categories`", $connection);
    if (!$query_meta) {
        die("Connection Failed: " . mysql_error());
    }

$meta_query_result = array();

while( $row = mysql_fetch_assoc($query_meta) ) {
    $meta_query_result[$row['id']] = array('url' => $row['url'], 'name' => $row['name'], 'title' => $row['title']);
}

The Echo Statement:

<h2><?php echo $meta_query_result[1]['name']; ?></h2>   
<h6><?php echo $meta_query_result[1]['title']; ?></h6>

This allows me to choose the row and the column I want to display.

How can I redo this in MySQLI? Thanks in advance!

Answer 1

you need to add the connection on the opposite side with mysqli.

so // mysql_query($q, $db_connnect); // becomes // mysqli_query($db_connnect, $q);

Answer 2

Of course you should read documentation , because it looks the same (on first glance) as mysql but has little difference...

Next example should be good for you:

<?php

$db = new mysqli('localhost', 'root');
if ($db->connect_errno) {
    echo 'Connect failed: '.$db->connect_error;
    exit();
}
$db->select_db('test');
$cursor = $db->query('SELECT * FROM categories');
if ($db->error) {
    echo $db->error.PHP_EOL;
}
$meta_query_result = [];
while($row = $cursor->fetch_assoc()){
    $meta_query_result[$row['id']] = [
        'url' => $row['url'],
        'name' => $row['name'],
        'title' => $row['title'],
    ];
}
$cursor->close();

Notice:And remember that mysql_query is deprecated as of PHP 5.5.0, use PDO instead.