MySQLi Repeat Row Depending on Column Quantity Value - php

Question

I have created a simple SQL statement to display which products customers have purchased from a woo commerce store.
This is working great but i'm struggling to find a SQL function that repeats rows based on a value, maybe one doesn't exist and PHP is required, any help would be great.
Thanks
CURRENT VIEW
ORDER ID. | PRODUCT NAME. | QTY
-------------------------------------
123 | APPLE | 3
124 | ORANGE | 2
125 | PEAR | 1
DESIRED VIEW
ORDER ID. | PRODUCT NAME. | QTY
-------------------------------------
123 | APPLE | 3
123 | APPLE | 3
123 | APPLE | 3
124 | ORANGE | 2
124 | ORANGE | 2
125 | PEAR | 1
CODE
<?php
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT wppc_wc_customer_lookup.customer_id, wppc_wc_customer_lookup.first_name,
wppc_wc_customer_lookup.last_name, wppc_wc_customer_lookup.email,
wppc_wc_order_stats.customer_id, wppc_wc_order_stats.total_sales,
wppc_wc_order_stats.order_id, wppc_wc_order_stats.date_created, wppc_wc_order_stats.status,
wppc_woocommerce_order_items.order_id, wppc_woocommerce_order_items.order_item_name,
wppc_woocommerce_order_items.order_item_id, wppc_woocommerce_order_itemmeta.order_item_id,
wppc_woocommerce_order_itemmeta.meta_id, wppc_woocommerce_order_itemmeta.meta_key,
wppc_woocommerce_order_itemmeta.meta_value FROM wppc_wc_customer_lookup
LEFT JOIN wppc_wc_order_stats ON wppc_wc_customer_lookup.customer_id =
wppc_wc_order_stats.customer_id
LEFT JOIN wppc_woocommerce_order_items ON wppc_wc_order_stats.order_id =
wppc_woocommerce_order_items.order_id
LEFT JOIN wppc_woocommerce_order_itemmeta ON wppc_woocommerce_order_items.order_item_id =
wppc_woocommerce_order_itemmeta.order_item_id
WHERE wppc_woocommerce_order_itemmeta.meta_key = '_qty' AND
wppc_woocommerce_order_items.order_item_name = 'Product Name' AND
wppc_wc_order_stats.status = 'wc-completed'
ORDER BY wppc_wc_order_stats.date_created DESC";
$result = $conn->query($sql);
echo "<table border=\"1\"><tr>";
echo "<tr><th>Order ID</hr><th>First Name</hr><th>Last Name</hr><th>Email</hr><th>Total</hr>
<th>Order Date</hr><th>Product Name</hr><th>Quantity</hr>";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
echo "<tr><td>".$row["order_id"]. " </td><td> " .$row["first_name"] . " </td><td> " .
$row["last_name"] . " </td> <td> " . $row["email"] . " </td><td> &pound".$row["total_sales"]
. " </td> <td>".$row["date_created"] . " </td> <td> ".$row["order_item_name"] . " </td> <td>
".$row["meta_value"] . " </td></tr> ";
}
} else {
echo "0 results";
}
echo "</table>";
$conn->close();
?>
This is working great but i'm struggling to find a SQL function that repeats rows based on a value, maybe one doesn't exist and PHP is required, any help would be great.

Answer 1

the idea is to make multiple select queries with different where clauses;
for instance in this case we need query like this:
SELECT * FROM table WHERE QTY > 0
UNION ALL
(SELECT * FROM table WHERE QTY > 1)
UNION ALL
(SELECT * FROM table WHERE QTY > 2)
ORDER BY `ORDER ID`
so we can create mysql procedure to generate such query depending on maximum qty like so
CREATE PROCEDURE GetAllProducts()
BEGIN
select max(QTY) - 1 into #maxQty from table;
set #resQry = 'SELECT * FROM table WHERE QTY > 0';
set #i = 0;
label1:
LOOP
IF #i = #maxQty THEN
leave label1;
END IF;
SET #i = #i + 1;
SET #resQry = CONCAT(#resQry, ' UNION ALL (SELECT * FROM table WHERE QTY > ', #i, ')');
END LOOP label1;
SET #resQry = CONCAT(#resQry, ' ORDER BY `ORDER ID`');
PREPARE stmt FROM #resQry;
EXECUTE stmt;
END;
and then you can call this procedure
CALL GetAllProducts();

Answer 2

If you are running MySQL 8.0, you can do this with a recursive query. Starting from your existing query, that would be:
with recursive
data as ( <... your query goes here ...> ),
rcte as (
select order_id, product_name, qty, 1 rn from data
union all
select order_id, product_name, qty, rn + 1 from rcte where rn < qty
)
select order_id, product_name, qty from rcte
In earlier versions, you could use a table of numbers. Here is an example that would quantities up to 3:
select d.*
from ( <... your query goes here ...> ) d
inner join (select 1 qty union all select 2 union all select 3) n
on n.qty <= d.qty
You can expand the subquery with more union alls to handle greater quantities.