date comparison weirdness

[thameslink]

I'm new to php & mysql

 

This has got me baffled

can anyone help me to understand why

 

 

select curdate();
+------------+
| curdate()  |
+------------+
| 2011-02-10 |
+------------+
1 row in set (0.00 sec)

 

Ok I understand that

now,

 

select DATE_FORMAT(CURDATE(),'%Y-%d-%m');
+-----------------------------------+
| DATE_FORMAT(CURDATE(),'%Y-%d-%m') |
+-----------------------------------+
| 2011-10-02                        |
+-----------------------------------+
1 row in set (0.00 sec)

Ok good I get that bit, seems to work exactly as I'd expect.

 

Now how come

mysql_query("UPDATE LOW_PRIORITY jos_vm_product SET product_in_stock = product_in_stock + '$product_quantity'
WHERE STR_TO_DATE(product_sku,'%Y-%d-%m') = CURDATE() AND product_sku = '$order_item_sku'") or
die(mysql_error());

 

produces

2812 cancelled 1 tickets sku was 2011-10-02 
1 tickets released into 2011-10-02 
Affected rows 1

 

Why does it match it without DATE_FORMAT()

 

and how can I make UPDATE rows where the STR_TO_DATE >= CURDATE()

 

 

Thanks

[Pikachu2000]

Your product SKU number in the table is a date?