Date Query Generator

How to use this query

SELECT * FROM table_name WHERE name LIKE '%John%' AND DATE BETWEEN '2017-03-02' AND '2017-03-11'

Using backend PHP Script

$dt1=$_POST['dt1'];
$dt2=$_POST['dt2'];

if(strlen($dt1) >5){ // if from date is filled
$date = new DateTime($dt1);
$dt1=$date->format('Y-m-d'); // To match MySQL date format
$sql= " AND dt >='$dt1'  " ;
}

if(strlen($dt2) >5){ // if to date is filled
$date = new DateTime($dt2);
$dt2=$date->format('Y-m-d'); // To match MySQL date format
$sql= " AND dt <= '$dt2'  " ;
}

if(strlen($dt1) >5 and strlen($dt2>5)){ // if both dates are  filled
$sql= " AND dt between  '$dt1' AND '$dt2'  " ;
}

$sql=preg_replace("/AND/","WHERE",$sql,1); // Remove first  AND with WHERE 

"SELECT FROM table_name $sql "

JQuery Date picker tutorial