<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* verifica a conexão */
if (mysqli_connect_errno()) {
    printf("Conexão falhou: %s\n", mysqli_connect_error());
    exit();
}
$query = "SELECT Name, SurfaceArea from Country ORDER BY Code LIMIT 5";
if ($result = mysqli_query($link, $query)) {
    /* Obtém informação do campo para todos os campos */
    while ($finfo = mysqli_fetch_field($result)) {
        printf("Name:     %s\n", $finfo->name);
        printf("Table:    %s\n", $finfo->table);
        printf("max. Len: %d\n", $finfo->max_length);
        printf("Flags:    %d\n", $finfo->flags);
        printf("Type:     %d\n\n", $finfo->type);
    }
    mysqli_free_result($result);
}
/* fecha a conexão */
mysqli_close($link);
?>
    
   Os exemplos acima produzirão:
Name:     Name
Table:    Country
max. Len: 11
Flags:    1
Type:     254
Name:     SurfaceArea
Table:    Country
max. Len: 10
Flags:    32769
Type:     4