1
Do full nodes verify the entire transaction chain up to coinbase when verifiying a single transaction to be included on the block which they are working on ?
1
Do full nodes verify the entire transaction chain up to coinbase when verifiying a single transaction to be included on the block which they are working on ?
2
They achieve the same result as if they did this, though not by actually doing it. (There are a number of obvious optimizations, for example, maintaining an indexed database of unspent outputs.)