Rollback counters for step records of a database
View Patent ↗A rollback record may be created for each step identifier (ID). The rollback record indicates how many times the step record identified by the step ID has been rolled back during operation of the database. The rollback record may be stored in a periodic save record (PSR), separate from or stored in an audit trail containing the step records. By processing the rollback records in the periodic save record during a recovery, a database may identify a time on an audit trail for initiating a recovery prior to the last resume point for a step without going back in the audit trail to a time before the initial start of the step.
1. A method, comprising:
recording one or more transaction updates to a database, wherein recording comprises assigning to a transaction update a step-id, in which the database is configured to record a step-id in at least two different step-id formats;
performing a first rollback of database processing on the database using at least one transaction update with assigned step-id, in which the database is capable of performing a first rollback with either of the at least two different step-id formats;
recording a number of times the one or more transaction updates are rolled back; and
recovering the database using the one or more transaction updates without applying updates previously rolled back in the first rollback;
wherein the at least two different step-id formats include:
a step-id formatted with an identification number set to a time, in a coordinated universal time (UTC) format, that does not change with seasonal offsets and a unique transaction identification value appended to the identification number;
a step id formatted with a time which is not formatted in coordinated universal time (UTC) format, a sequence number, and an advance number; and
wherein the step of recording the first rollback comprises incrementing a rollback counter in a rollback record, and in which the step of performing the recovery comprises using the rollback counter to identify portions of the step that rolled back.
2. The method of claim 1 , further comprising generating an error when the rollback counter reaches a predetermined value.
3. The method of claim 1 , further comprising:
recording second transaction updates; and
performing a second rollback of database processing on the database using the second transaction updates.
4. The method of claim 1 , further comprising appending the recorded number of times to a periodic save record.
5. A computer program product, comprising:
a non-transitory computer readable medium comprising:
code to record one or more transaction updates to a database, wherein recording comprises assigning to a transaction update a step-id, in which the database is configured to record a step-id in at least two different step-id formats; that comprises an identification number set to a time, in a coordinated universal time (UTC) format, that does not change with seasonal offsets and a unique transaction identification value appended to the identification number;
code to perform a first rollback of database processing on the database using at least one transaction update with assigned step-id, in which the database is capable of performing a first rollback with either of the at least two different step-id formats;
code to record a number of times the one or more transaction updates are rolled back; and
code to recover the database using the one or more transaction updates without applying updates previously rolled back in the first rollback; and
code to increment a rollback counter in a rollback record, and in which the step of performing the recovery comprises using the rollback counter to identify portions of the step that rolled back;
wherein the at least two different step-id formats include:
a step-id formatted with an identification number set to a time, in a coordinated universal time (UTC) format, that does not change with seasonal offsets and a unique transaction identification value appended to the identification number; and
a step id formatted with a time which is not formatted in coordinated universal time (UTC) format, a sequence number, and an advance number.
6. The computer program product of claim 5 , in which the medium further comprises code to generate an error when the rollback counter reaches a predetermined value.
7. The computer program product of claim 5 , in which the medium further comprises code to record second transaction updates and code to perform a second rollback of database processing on the database using the second transaction updates.
8. The computer program product of claim 5 , in which the medium further comprises code to append the recorded number of times to a periodic save record.
9. An apparatus, comprising:
a memory for storing a database; and
a processor coupled to the memory, in which the processor is configured:
to record one or more transaction updates to a database, wherein recording comprises assigning to a transaction update a step-id, in which the database is configured to record a step-id in at least two different step-id formats; that comprises an identification number set to a time, in a coordinated universal time (UTC) format, that does not change with seasonal offsets and a unique transaction identification value appended to the identification number;
to perform a first rollback of database processing on the database using at least one transaction update with assigned step-id, in which the database is capable of performing a first rollback with either of the at least two different step-id formats;
to record a number of times the one or more transaction updates are rolled back;
to recover the database using the one or more transaction updates without applying previously rolled back updates; and
to increment a rollback counter in a rollback record, and in which the step of performing the recovery comprises using the rollback counter to identify portions of the step that rolled back;
wherein the at least two different step-id formats include:
a step-id formatted with an identification number set to a time, in a coordinated universal time (UTC) format, that does not change with seasonal offsets and a unique transaction identification value appended to the identification number; and
a step id formatted with a time which is not formatted in coordinated universal time (UTC) format, a sequence number, and an advance number.
10. The apparatus of claim 9 , in which the processor is further configured to generate an error when the rollback counter reaches a predetermined value.
11. The apparatus of claim 9 , in which the processor is further configured to record second transaction updates and to perform a second rollback of database processing on the database using the second transaction updates.
12. The apparatus of claim 9 , in which the processor is further configured to append the recorded number of times to a periodic save record.