MySQL / PHP检索项目在第二个表中出现的次数

first time here ...

I have an issue in MySQL:

I have a table 'products' with some fields like product_id, itemcode, label, price, .... There is also a second table 'inventory' that has some common fields with the first field. The field 'itemcode' is the easiest to compare both tables.

products has from every 'itemcode'-item only one appearance. Inventory, however, has them multiple times.

What I need to do: I need to output how many times each 'itemcode' from 'products' appears in 'inventory'. What would be the best way to do so?

example

products
  itemcode
  AA2244G
  AB2245G
  AC2246G
  AD2247G
  AE2248G

inventory
  itemcode
  AA2244G
  AA2244G
  AB2245G
  AC2246G
  AC2246G
  AC2246G
  AE2248G

Output
 AA2244G 2x
 AB2245G 1x
 AC2246G 3x
 AD2247G 0x
 AE2248G 1x
SELECT  a.itemcode, CONCAT(COUNT(b.itemcode), 'x') totalCount
FROM    products a 
        LEFT JOIN inventory b
            ON a.itemcode = b.itemcode
GROUP BY a.itemcode