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Message Posted: Fri, 23 Sep 2005 @ 17:04:34 GMT
Subj: | | Re: Automated PPI Maintenance |
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From: | | Spaleny Ivo |
| slow performance for the Drop partition step. | |
1. Drop of a partition is a change of DDL only.
2. If a dropped partition is not empty, rows are moved to a default "UNKNOWN" partition. This is a new physical insert/delete operation and can
take some time to move and update primary index pointers in secondary indexes. It is the worst method.
3. Secondary indexes are stored without real partitioning, just with a primary index pointer with partitioning information. Even if rows from a
being-deleted partition are deleted almost immediately, secondary indexes must be reordered for all deleted values. It can be a time-consuming
task.
Best regards,
Ivo Spaleny
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