如何将datepicker插入数据库

Question

我需要阅读“＃month;＆＃39;来自表site_salmonusage。 Here是site_salmonusage中的数据示例。然后我需要计算数据是否存在，如果存在，那么我需要更新该月份的所有数据＆＃39;。如果不存在，它将插入。

if ($_POST['register']){
$entry_id=$_POST["entry_id"];
$storenum = $_POST["storenum"];
$store_name=$_POST["store_name"];
$month = $_POST["month"];
$usage = $_POST["usage"];

$remove=mysqli_query($con,"SELECT COUNT(*)  As count FROM site_salmonusage WHERE month='$month' AND storenum='$storenum'");

$row=mysqli_fetch_array($remove);

if($row['count']==1){

    $add1 = "UPDATE site_salmonusage
SET  usage='$usage'
WHERE storenum='$storenum' AND month='$month'";
} 

else if($row['count']==0){
$add = "INSERT INTO site_salmonusage (storenum, month, usage)
VALUES ('$storenum','$month',$usage')";
}
else {
    $del= "DELETE  FROM site_salmonusage WHERE month='$month'"; 
    $adding="INSERT INTO site_salmonusage (storenum,month,usage)
    VALUES ('$storenum','$month','$usage')";
}

这是我的php。但是在提交按钮后，它不会插入到数据库中。