Useful Oracle tools – DBCOMP

Getting lost writes (e.g. ORA-00752: recovery detected a lost write of a data block) is one of the worst DBA’s nightmares. There are a lot of very important questions popping up. Apart from the obvious ones on how to solve the problems reported (hopefully without any data loss), there are many others. For instance – can I rely on my current software and/or hardware stack? Or maybe lost writes were introduced before and I should be fine with what I have? What about other lost writes which are dormant and not yet detected? Fortunately, since Oracle 12.2 version, the last one can be easily answered.

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Be careful with ‘save state’ in Data Guard configuration

Users are complaining that from time to time they are connecting to standby database which is opened read-only, instead to primary opened also for writing. What can be the root cause?

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