$contents = file_get_contents("foo.txt.001");
     $pollfields = explode(',', $contents);


foreach ($pollfields as $key) {


            $sql = "INSERT INTO table (`row`) VALUES ('".$key."')";
            if ($conn->query($sql) === TRUE) {
            echo "New record created successfully";
        } else {
            echo "Error: " . $sql . "<br>" . $conn->error;
        }
}
    <form action="submit.php" method="post">
        <div class="input-group" >

            <span class="input-group-btn">
                <br>
                <br>
                <center><button type="submit" class="btn btn-primary">Submit</button></center>

            </span>
        </div>
    </form>