How can I use mysqli_fetch_array() twice?

You should always separate data manipulations from output.

Select your data first:

$db_res = mysqli_query( $db_link, $sql );
$data   = array();
while ($row = mysqli_fetch_assoc($db_res))
{
    $data[] = $row;
}

Note that since PHP 5.3 you can use fetch_all() instead of the explicit loop:

$db_res = mysqli_query( $db_link, $sql );
$data   = $db_res->fetch_all(MYSQLI_ASSOC);

Then use it as many times as you wish:

//Top row
foreach ($data as $row)
{
    echo "<td>". $row['Title'] . "</td>";
}

//leftmost column
foreach ($data as $row)
{
    echo "<tr>";
    echo "<td>". $row['Title'] . "</td>";
    .....
    echo "</tr>";
}

Yes. mysqli_fetch_array() moves the pointer forward each time you call it. You need mysqli_data_seek() to set the pointer back to the start and then call mysqli_fetch_array() again.

So before calling the function a second time, do:

mysqli_data_seek($db_res, 0);

You don't need the while loop and you don't need to use mysqli_fetch_array() at all!

You can simply loop on the mysqli_result object itself many times. It implements Traversable interface that allows it to be used in foreach.

//Top row
foreach($db_res as $row) {
    echo "<td>". $row['Title'] . "</td>";
}

//leftmost column
foreach($db_res as $row) {
    echo "<tr>";
    echo "<td>". $row['Title'] . "</td>";
    .....
    echo "</tr>";
}

However, you should separate your DB logic from your display logic and to achieve this it is best to use fetch_all(MYSQLI_ASSOC) in your DB logic to retrieve all records into an array.

If you fetch all the data into an array, you can loop that array as many times as you want.

$data = $db_res->fetch_all(MYSQLI_ASSOC);

foreach($data as $row) {
    // logic here...
}

How can I use mysqli_fetch_array() twice?

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