Question about COUNT(*)

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Hi,

Let's say that I have 2 tables: client and sales
---------------------------
| client_id | client_name |
---------------------------
|         1 | John        |
|         2 | Mark        |
|         3 | Luke        |
|         4 | Matthew     |
---------------------------

-------------------------------------
| sale_id | client_id | sale_item   |
-------------------------------------
|       1 |         1 | Book        |
|       2 |         1 | Pencil      |
|       3 |         1 | Pen         |
|       4 |	  2 | Ruler       |
|       5 |         2 | Bag         |
|       6 |         3 | Hat         |
-------------------------------------

How can I have total purchased items for each of the client like this table
below since COUNT(*) is only for non-NULL values?
-----------------------
| client_name | total |
-----------------------
| John        |     3 |
| Mark        |     2 |
| Luke        |     1 |
| Matthew     |     0 |
-----------------------

I've tried: SELECT client.name, COUNT(*) total
	    FROM client, sales
	    WHERE client.client_id = sales.client_id
	    GROUP BY client.client_name
	    ORDER BY total DESC

and it returns:
-----------------------
| client_name | total |
-----------------------
| John        |     3 |
| Mark        |     2 |
| Luke        |     1 |
-----------------------

How can I have Matthew who does't purchase anything on the list?
Your help is much appreciated. Thanks.


Erick Wellem

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