insertion and updation

mysqli_query($con, "SET AUTOCOMMIT=0");
mysqli_query($con,"START TRANSACTION");
$insert1 = mysqli_query($con,"INSERT INTO jobfairs(jobid,employer_emailid,jobtitle,company,companyprofile,companywebsite,location,catagory,position,qualification,keyskills,description,experience,lastdate,salary,work_type,address)
            VALUES ('$jobid','$employer_emailid','$valid_jobtitle','$company','$companypro','$companywebsite','$location','$catagory', '$position','$qualification','$keyskills1','$description','$experience','$lastdate','$annualsalary','$job_preference','$companyaddress')");
foreach($t as $val)
{
    //print_r($t);
$insert3=mysqli_query($con,"INSERT INTO notification(jobid,jobtitle,user_email,status) VALUES ('$jobid','$valid_jobtitle','$val','new')");
}
$insert2 = mysqli_query($con,"INSERT INTO job_posted(job_id,user_mail,job_type,counter,status)VALUES ('$jobid','$employer_emailid','$catagory',1,'new')");

if($insert1 && $insert2 && (!$insert3 || $insert3 ) ){
    mysqli_query($con,"COMMIT");
} else {
    mysqli_query($con,"ROLLBACK");
}

$course_q= mysqli_query($con,"SELECT LAST_INSERT_ID() AS insert_id FROM jobfairs");
$c = mysqli_fetch_assoc($course_q);
$lid=$c['insert_id'];
$updated_jobid="$jobid".$c['insert_id'];
$upjoid=mysqli_query($con,"UPDATE jobfairs SET jobid='$updated_jobid' WHERE id='$lid'");
$upresult = $con->query($upjoid);

$course_q1= mysqli_query($con,"SELECT LAST_INSERT_ID() AS ins_id FROM job_posted");
$c1 = mysqli_fetch_assoc($course_q1);
$lid1=$c1['ins_id'];
$updated_jobid1="$jobid".$c['insert_id'];
$upjoid1=mysqli_query($con,"UPDATE job_posted SET job_id='$updated_jobid' WHERE id='$lid1'");
$upresult1 = $con->query($upjoid1);

        if(!empty($t)){
$updated_jobid2="$jobid".$c['insert_id'];
$upjoid2=mysqli_query($con,"UPDATE notification SET jobid='$updated_jobid' WHERE jobid='$jobid'");
$upresult2 = $con->query($upjoid2);
        }
mysqli_query($con, "SET AUTOCOMMIT=1");