Common Errors Series

I will be publishing some "Common Errors" by DBAs and Developers. These errors occur in the course of performance tuning or database or instance configuration or in understanding oracle concepts.

The first of these is about using a count(*) or a count(1) as a wrapper around a user's query when attempting performance tuning.

The second of these is about specifying NOLOGGING as a Hint when executing DML.

The third of these is about NOLOGGING and Indexes.

The fourth is about ARRAYSIZE.

The fifth is about Not reviewing the alert.log and trace files.

The sixth is about Not collecting metrics.

The seventh is about the behaviour "We killed the job because it was hung".

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