mysql - Rownum の問題を表示する MySQL

Question

私はこのクエリを持っています:

SET @row_num = 0;
SELECT
(SELECT @row_num := @row_num + 1) AS itempurchase_code,
(SELECT supplier_code FROM qa_items_purchases a WHERE a.item_invoicecodesupplier = b.item_invoicecodesupplier GROUP BY supplier_code ORDER BY COUNT(*) DESC LIMIT 1) AS supplier_code, 
(SELECT user_code FROM qa_items_purchases a WHERE a.item_invoicecodesupplier = b.item_invoicecodesupplier GROUP BY user_code ORDER BY COUNT(*) DESC LIMIT 1) AS user_code,
22 AS status_code,
item_invoicecodesupplier AS item_invoicecodesupplier,
(SELECT itempurchase_date FROM qa_items_purchases a WHERE a.item_invoicecodesupplier = b.item_invoicecodesupplier GROUP BY itempurchase_date ORDER BY COUNT(*) DESC LIMIT 1) AS itempurchase_date
FROM qa_items_purchases b 
GROUP BY (item_invoicecodesupplier) 
ORDER BY itempurchase_code;

私はこの結果を得る：

( 2)itempurchase_code列がない場合、数字を順番に表示するにはどうすればよいですか?