Method and apparatus for improved transaction recovery

A method for recovering after a premature termination of a transaction, the method comprising the computer implemented steps of:

• starting execution of a new transaction after the premature termination of the transaction and before all updates made by the prematurely terminated transaction have been undone;
• when the new transaction requests access to a resource, determining that the resource belongs to the prematurely terminated transaction;
• and
• in response to determining that the resource belongs to the prematurely terminated transaction, undoing one or more changes made by the prematurely terminated transaction.

A computer-readable medium having stored thereon sequences of instructions for recovering after a crash of an instance of a database, wherein one or more transactions were active when the instance crashed, the sequences of instructions including instructions which, when executed by a processor, cause the processor to perform the steps of:

• finding transaction information that corresponds to one or more transactions that existed in the instance;
• determining, based on the transaction information, whether the transactions that existed in the instance were active when the instance crashed;
• if one or more transactions were active when the instance crashed, then updating the transaction information to indicate that the one or more transactions that were active when the instance crashed are dead;
• making the database available to users after updating the transaction information and before undoing all of the updates performed by the one or more transactions that were active when the instance crashed;
• executing a new transaction;
• when the new transaction requests access to a resource, determining that the resource belongs to a particular transaction that was active when the instance crashed;
• and
• in response to determining that the resource belongs to the particular transaction that was active when the instance crashed, undoing one or more changes made by the particular transaction.