function pub_column_exists(
    mysqli $conn,
    string $table,
    string $column
): bool {
    $t = str_replace('`', '``', $table);
    $c = mysqli_real_escape_string($conn, $column);

    $q = mysqli_query(
        $conn,
        "SHOW COLUMNS FROM `{$t}` LIKE '{$c}'"
    );

    if (!$q) {
        return false;
    }

    $exists = mysqli_num_rows($q) > 0;

    mysqli_free_result($q);

    return $exists;
}


/*
|--------------------------------------------------------------------------
| mysqlnd-safe prepared statement helper
|--------------------------------------------------------------------------
*/

function pub_stmt_fetch_assoc(
    mysqli_stmt $stmt
): ?array {

    if (
        function_exists(
            'mysqli_stmt_get_result'
        )
    ) {
        $result =
            mysqli_stmt_get_result(
                $stmt
            );

        if (!$result) {
            return null;
        }

        $row =
            mysqli_fetch_assoc(
                $result
            ) ?: null;

        mysqli_free_result(
            $result
        );

        return $row;
    }

    $meta =
        mysqli_stmt_result_metadata(
            $stmt
        );

    if (!$meta) {
        return null;
    }

    $fields =
        mysqli_fetch_fields(
            $meta
        );

    mysqli_free_result(
        $meta
    );

    if (!$fields) {
        return null;
    }

    $values = [];
    $refs = [];

    foreach ($fields as $field) {
        $name = (string)$field->name;

        $values[$name] = null;
        $refs[] =& $values[$name];
    }

    if (
        !mysqli_stmt_bind_result(
            $stmt,
            ...$refs
        )
    ) {
        return null;
    }

    if (
        mysqli_stmt_fetch(
            $stmt
        ) !== true
    ) {
        return null;
    }

    $row = [];

    foreach (
        $values as
        $key => $value
    ) {
        $row[$key] = $value;
    }

    return $row;
}