Patent ID: 8706619

Claim:
A non-transitory computer-readable medium embodying a program executable in a computing device, the program comprising: code that receives a first transaction to update an account balance associated with an account stored in a data table in a data store, the account including an account constraint that specifies that the account balance cannot be below zero and the first transaction including a first amount by which to update the account balance; code that initiates a first attempt to obtain an exclusive lock on the data table in the data store; code that inserts the first transaction into a spillover table in response to a failure of the first attempt to obtain the exclusive lock on the data table and further in response to a satisfaction of a condition that the first amount is not a negative amount, the spillover table configured to store at least one other transaction; code that receives a second transaction including a second amount by which to update the account balance, the second amount being a negative amount; code that initiates at least one second attempt to obtain the exclusive lock on the data table of the data store; code that updates the account balance in the data table with at least one amount from the at least one other transaction stored in the spillover table, the at least one other transaction having a timestamp that is earlier than a timestamp associated with the second transaction when the exclusive lock is obtained; and code that updates the account balance in the data table with the second amount from the second transaction when the exclusive lock on the data table is obtained.