Hakan factor
The Hakan factor is used to unique map rows in a Bitmap Index to the rows in the base table. This factor is related to the max number of rows that can be stored in a single block of a table. Several factors like the column type and not null constraints influence the Hakan factor. The factor will also be recalculated when a table is modified until there is the first bitmap Index is created. Than the Hakan factor has to be protected for the existing bitmap indexes.
If a new table created to exchange data with the partitioned table, with a table layout, that include columns added after the bitmap index creation on the partitioned table, will most likely result in a different Hakan factor.
Errors
If the Hakan Factor do not match during exchange partitions, the prognosis is either of the error messages below:
- ORA-14642: “Bitmap index mismatch for tables in ALTER TABLE EXCHANGE PARTITION”
- ORA-14643: “Hakan factor mismatch for tables in ALTER TABLE EXCHANGE PARTITION”
The error can appear only if you exchange a partition with bitmap indexes
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