Rollback
- Thread starter gogaak
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Rollback in Access?
If you have a situation where you did a BEGIN TRANSACTION, then do a ROLLBACK rather than COMMIT, I think your limit is a double-barreled problem. The way Access does this is it makes copies of the new records that will replace the previous versions. Then, the COMMIT does a replace, dropping the prior records, and the ROLLBACK drops the updated records, keeping the prior records. In the COMMIT change, Access just updates the record pointers that are part of its implementation of the table. In either case, the pointers to the dropped records are marked for delete. At the next compaction, their space is reclaimed.
The records are kept on disk (I think) and the dynamic list of pointers is in memory. So whichever one of those runs out first is the answer to your limit. Your memory limit for this case is virtual memory, which is in turn controlled by available swap-file space. Your disk limit is whatever it is, or either 1 or 2 Gb, depending on Access version, 'cause the .MDB size cannot exceed the limit for your version. See Help files, either Limits (A97) or Specifications (A2K and later) for the exact limit.
If you meant any OTHER kind of rollback than BEGIN/ROLLBACK type actions, please specify.
If you have a situation where you did a BEGIN TRANSACTION, then do a ROLLBACK rather than COMMIT, I think your limit is a double-barreled problem. The way Access does this is it makes copies of the new records that will replace the previous versions. Then, the COMMIT does a replace, dropping the prior records, and the ROLLBACK drops the updated records, keeping the prior records. In the COMMIT change, Access just updates the record pointers that are part of its implementation of the table. In either case, the pointers to the dropped records are marked for delete. At the next compaction, their space is reclaimed.
The records are kept on disk (I think) and the dynamic list of pointers is in memory. So whichever one of those runs out first is the answer to your limit. Your memory limit for this case is virtual memory, which is in turn controlled by available swap-file space. Your disk limit is whatever it is, or either 1 or 2 Gb, depending on Access version, 'cause the .MDB size cannot exceed the limit for your version. See Help files, either Limits (A97) or Specifications (A2K and later) for the exact limit.
If you meant any OTHER kind of rollback than BEGIN/ROLLBACK type actions, please specify.
