通过链接将多行插入数据库

I am quite new in php and mysql. I was trying to insert multiple (unknown ) number of rows into mysql database. The data is posted into the table through a link - http://localhost:81/logdata.php?CtrlID=3842&DateTime=2017-05-18+11%3A45%3A23&Bat=50.2&LVSD=1&Indt=29.4&Outdt=32.8&submit

The following code works perfect as long as a single row is posted. But I have no idea how to insert several rows together and how the link should look like. Actually rows containing data are formed and stored in a Microcontroller. I am sending the data with the help of GPRS. The controller successfully sending one row at a time, the data is correctly recorded in mysql database. But I am struggling to send several rows together. I would highly appreciate any suggestion.

<?php
$servername = "localhost";
$username = "root";
$password = ""; //your pwd
$dbname = "mirzu";

// Create connection
$conn = new mysqli($servername, $username, $password,$dbname);
if($conn){
    echo 'Successfully Connected database.';
     }

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

//if(isset($_GET['submit'])){   //
    $ID = $_GET['CtrlID'];
    $DateTime = $_GET['DateTime'];
    $battery = $_GET['Bat'];
    $LVSD = $_GET['LVSD'];
    $IndoorT = $_GET['Indt'];
    $OutdoorT = $_GET['Outdt'];

$totalCtrlID = sizeof($ID);

for($i=0;$i<$totalCtrlID;$i++) {

    $InsCtrlID = [$ID][$i]; 
    $InsDateTime = [$DateTime][$i];
    $Insbattery = [$battery][$i];
    $InsLVSD = [$LVSD][$i];
    $InsIndoorT = [$IndoorT][$i];
    $InsOutdoorT = [$OutdoorT][$i];


 $query = "INSERT INTO btsdata (CtrlID,DateTime,Batt,LVSD,IndT,OutdT)". 
"VALUES  ('$InsCtrlID','$InsDateTime','$Insbattery','$InsLVSD','$InsIndoorT','$InsOutdoorT');";

}

if (mysqli_query($conn,  $query)) {
    echo "New record created successfully into database";
} else {
    echo "Error: " .  $query . "<br>" . mysqli_error($conn);
}
//}
mysqli_close($conn);
?> 

Two records the query will become:

 INSERT INTO TABLE (column1, column2) VALUES ('data', 'data'), ('data', 'data')

Same as a more than two record.

 INSERT INTO tbl_name
        (a,b,c)
    VALUES
        (1,2,3),
        (4,5,6),
        (7,8,9);