Conclusion


The database administrator has answered most of the questions posed at the start of this scenario. The only unknown question is why the system suddenly encountered this slowdown after performing normally, and what caused this problem. The database administrator contacts the application support team and finds out that their test environment has a DEPT_ACCESS table that is much smaller than in production. This explains why the lack of indexes did not cause an issue earlier.

Answers to the questions that the database administrator had for the problem: