Database recovery can be performed in substantially constant time. From a database transaction log, the state of one or more transactions is identified including those that were active at a time of a crash but not committed. Transactions can be reapplied sequentially starting from the beginning of a last successful checkpoint to the end of the transaction log. Uncommitted user transactions are not undone synchronously, but simply marked as aborted. Subsequently, versions of affected data elements can be reverted back to a prior saved version asynchronously.