SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1922-1' for key 'IDX_STOCK_PRODUCT'

the message means you are doing another insert with the same combination of columns that are part of the IDX_STOCK_PRODUCT, which seams to be defined as UNIQUE. If it is so, it doesn't allow to enter same combination (it seems like it consists of two fields) twice.

If you are inserting records, make sure you are picking brand new record id or that the combination of record id and the other column is unique.

Without detailed table structure and your code, we can hardly guess whats going wrong.

Many time this error is caused when you update a product in your custom module's observer as shown below.

class [NAMESPACE]_[MODULE NAME]_Model_Observer
{
    /**
     * Flag to stop observer executing more than once
     *
     * @var static bool
     */
    static protected $_singletonFlag = false;

    public function saveProductData(Varien_Event_Observer $observer)
    {
        if (!self::$_singletonFlag) {
            self::$_singletonFlag = true;

            $product = $observer->getEvent()->getProduct();
             //do stuff to the $product object
            // $product->save();  // commenting out this line prevents the error
            $product->getResource()->save($product);
    }
} 

Hence whenever you save your product after updating some properties in your module's observer use $product->getResource()->save($product) instead of $product->save()