1064 message in Google shopping plugin

-- HikaShop version -- : 2.3.4
-- Joomla version -- : 3.3.6
-- Error-message(debug-mod must be tuned on) -- : You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') AND a.product_published=1 AND b.price_currency_id IN (1,2)' at line 1 SQL=SELECT a.*,b.* FROM bacjp_hikashop_product AS a LEFT JOIN bacjp_hikashop_price AS b ON a.product_id=b.price_product_id WHERE a.product_parent_id IN () AND a.product_published=1 AND b.price_currency_id IN (1,2)

Hello,
Recently I discovered that the Google shopping plugin didn't load to the merchant centre.
After trying to do this manualy I got this message:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use
near ') AND a.product_published=1 AND b.price_currency_id IN (1,2)' at line 1 SQL=SELECT a.*,b.* FROM bacjp_hikashop_product AS a LEFT JOIN bacjp_hikashop_price AS b ON a.product_id=b.price_product_id WHERE a.product_parent_id IN () AND a.product_published=1 AND b.price_currency_id IN (1,2)

Can you tell me what has occurred?
I found out that some items lost there retail price. These I have set again.
But still this message

Ok, do I need to do all these changes?
When do expect the next version to come?

I think this has done the trick

"Hi,
Ok, change the line:
$variantSearch[]=$element->product_id;
to:
$variantSearch[]=(int)$element->product_id;
in administrator/components/com_hikashop/classes/currency.php and that will fix the first error.

The google products XML should contain all the information you need.