Cannot get the proper set of data using PHP and MySQL - php

Question

I need to fetch data from DB in an array using PHP and MySQL. In my case I am having 1 set of data in the given condition but the same set of data is coming multiple times. I am providing my code below.
$pro_id=$_GET['pro_id'];
$userid=$_GET['user_id'];
$sql="
SELECT s.id,
s.voucher_code,
s.merchant,
s.date,
s.receiver,
s.sender,
s.serial_no,
s.image,
s.expired_date,
s.product_id,
c.status,
c.redeem_status,
sup.supplier_id,
sup.NAME,
a.NAME AS sender_name,
v.discount,
v.discount_type,
v.voucher_amount,
p.product_name AS pro_name
FROM db_send_evoucher_code s
INNER JOIN db_code c
ON s.voucher_code = c.total_voucher_code
INNER JOIN db_supplier sup
ON s.merchant = sup.supplier_id
INNER JOIN medilink_admin a
ON s.sender = a.admin_id
INNER JOIN db_voucher_code v
ON c.voucher_code_id = v.voucher_code_id
INNER JOIN db_product_info p
ON s.product_id = p.pro_id
WHERE s.receiver = '". $userid ."'
and s.product_id = '". $pro_id ."'";
$sqlqry = mysqli_query($con, $sql);
if (mysqli_num_rows($sqlqry) > 0) {
while ($row = mysqli_fetch_array($sqlqry)) {
if ($row['discount_type'] == 'Flat') {
$distype = 1;
}
if ($row['discount_type'] == 'percentage') {
$distype = 2;
}
$data['data'][] = $data['data'][] = array("voucher_code" => $row['voucher_code'], "send_by" => $row['sender_name'], "image" => $row['image'], "expired_date" => $row['expired_date'], "supplier_name" => $row['name'], "sending_date" => $row['date'], "supplier_id" => $row['supplier_id'], "discount" => $row['discount'], "product_id" => $row['product_id'], "product_name" => $row['pro_name'], "redeem_status" => $row['redeem_status'], "voucher_amount" => $row['voucher_amount'], "discount_type" => $distype, "imagepath" => $imagepath);
echo json_encode($data, JSON_UNESCAPED_SLASHES);
}
} else {
$data['data'] = array();
echo json_encode($data);
}
Here in the given condition I have one set of data inside DB but it's coming two times. Here is my output:
{"data":[{"voucher_code":"FIFLTBH8567","send_by":"Medilink","image":"glotnzgrqbyb9_97yw155165stt9_eneoji_l.jpg","expired_date":"22-02-2016","supplier_name":"Eneoji","sending_date":"2016-02-18 16:11:35","supplier_id":"9","discount":"20","product_id":"52","product_name":"Eneoji Fomentation Therapy","redeem_status":"0","voucher_amount":"2000","discount_type":2,"imagepath":"http://li120-173.members.linode.com/crm_beta/upload/"},{"voucher_code":"FIFLTBH8567","send_by":"Medilink","image":"glotnzgrqbyb9_97yw155165stt9_eneoji_l.jpg","expired_date":"22-02-2016","supplier_name":"Eneoji","sending_date":"2016-02-18 16:11:35","supplier_id":"9","discount":"20","product_id":"52","product_name":"Eneoji Fomentation Therapy","redeem_status":"0","voucher_amount":"2000","discount_type":2,"imagepath":"http://li120-173.members.linode.com/crm_beta/upload/"}]}

Answer 1

You should check if there is 2 lines with the same foreign key value in one of the inner joined table.
For ex,if you have 2 rows with total_voucher_code = "FIFLTBH8567" in table db_code, even if the reste of the row is different, you'll get this kind of unexpected result.

Answer 2

Try to write your SELECT statement as below
SELECT DISTINCT s.id,s.voucher_code,s.merchant etc...

Answer 3

Use distinct in your sql, so you don't get any duplicates rows:
$sql="select distinct s.id,s.voucher_code,s.merchant,s.date,s.receiver,s.sender,s.serial_no,s.image,s.expired_date,s.product_id,c.status,c.redeem_status,sup.supplier_id,sup.name,a.name AS sender_name,v.discount,v.discount_type,v.voucher_amount,p.Product_name AS pro_name
from db_send_evoucher_code s
INNER JOIN db_code c ON s.voucher_code=c.total_voucher_code
INNER JOIN db_supplier sup ON s.merchant=sup.supplier_id
INNER JOIN medilink_admin a ON s.sender=a.admin_id
INNER JOIN db_voucher_code v ON c.voucher_code_id=v.voucher_code_id
INNER JOIN db_product_info p ON s.product_id=p.pro_Id
where s.receiver='".$userid ."' and s.product_id='".$pro_id."'";