Setup - Using the ConsumerDirect store.
I have a scenario

Step 1> Registered to the store and added an item to the cart.Now cart shows 1 item
Step 2> logged out. Now cart shows 0 items.
Step 3> Added an item in the cart as a guest shopper. Now cart shows 1 item.
Step 4> logged in using the same id as in Step 1. Now cart shows 2 items.
Where is the mapping stored?.