CA IDMS/DB Audit fixes only physical integrity errors. Logical integrity errors cannot be fixed because CA IDMS/DB Audit does not know the logical basis used to store the data on the database.
For example, in Figure 2.40, the STUDENT-REPORTS set contains two record types: GR and DR. Each record type is sorted in descending order by year and grading period. DR records are stored whenever necessary and should occur in the set after the GR records.
Assume that one of the next pointers is broken. CA IDMS/DB Audit fixes the set as shown in Figure 2.41. If logically the DR records are to follow the GR records for the same year and grading period, then the "fixed" set occurrence is not in the correct logical sequence. Nevertheless, the physical integrity of the set is correct. Logical integrity can be fixed by a user program--a correction that may not have been possible before the physical integrity was fixed.
Figure 2.40: Physical Integrity Error
Figure 2.41: Physical Integrity and Logical Integrity
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