Patent ID: 7984015

Claim:
A computer-implemented method comprising steps of: a replay database server receiving commands that were recorded by an initial database server in response to said initial database server receiving said commands; and said replay database server executing said commands relative to a replay database in response to receiving said commands; wherein said initial database server executed said commands relative to an initial database that is separate from said replay database; wherein each command of said commands is a separate workload unit in a set of workload units; constructing a dependency graph of nodes in which each node represents a workload unit in said set of workload units; wherein each node in said dependency graph is associated with a separate system change number; wherein, within said dependency graph, each particular node's system change number is not before a system change number of any other node from which that particular node depends; executing, relative to the replay database, a commit operation that corresponds to a commit node associated with a pre system change number; at least partially in response to executing the commit operation, (a) setting a replay database system change number to post a system change number associated with the commit node, (b) using the dependency graph to determine a subset of two or more nodes that depend from a node that represents the commit operation, wherein each of the two or more nodes are associated with different system change numbers that are after the pre system change number but not after the replay database system change number, and (c) executing, relative to the replay database, all unexecuted workload units of all nodes in the subset; wherein the steps are performed by one or more computing devices.