With this behavior you can verify the items in the cart and check if are "In Stock" or "Out Of Stock".
This behavior checks the database table that holds the stock counts for the items that are in the cart to see if the item(s) are still available and put the result in a cart column to be used in your pages
Connection
Self explanatory
Product table
The table that holds the product we want to check.
IdProduct table field
This is the field in the table that corresponds to the ProductID that is in the cart.
Qty stock field
This is the actual field that holds the current inventory stock level
Cart IdProduct column
Set this to the cart column that contains the ProductID
Cart qty column
Set this to the cart column that contains the Product quantity
Out of Stock column
This is the cart column where put the quantity out of stock. If the quantity required is available this field will have value =0, otherwise the value will be the items out of stock
Behavior out of stock
Define what to do for the item out of stock, can be: None, Remove Item and Modify quatity. If the Modify Quantity option is selected the quantity of the out of stock items is rediced to the stock quantity
Redirect page
Specify the page you want to redirect users if an item is out of stock