Re: HELP-need gurus-Oracle Support conflicting answers

Doug Cowles wrote:

< Real life case study on DBA / OS file operations >

Nothing beats the manuals. After reading the 'story', I just read the Oracle SQL Reference 8.0 - ALTER DATABASE command out of curiosity and at face value it seems to contain 90-95% of all the information that was
'discovered' through the history of this story.

Seems that Oracle support, just like you or I, feel pressured into thinking through a problem and coming up with the answer which may or may not be the whole truth. Also, they will never know the complete history of an installation (unless .... - see ahead).

In the story, the datafile-still-in-data-dictionary could for all I know have been because a checkpoint was not performed on the datafile before it was taken offline (apparently this is the default behaviour of the ALTER DATABASE DATAFILE 'xyz.ora' OFFLINE DROP).

Also, the issue of media recovery (i.e. why Oracle mandates this in these circumstances) is also clearly explained in the manual.

One lesson I have learned from this story is that the official documentation seems to come out on top. If you coupled this fact with a
'rule of thumb' where each DBA updated a kind of paper log of what SQL
has actually been issued against a database - studying this log and the relevant sections of the documentation should be a winning combination in times of DBA-induced trouble. Additionally, the history of an installation as expressed in this log could be passed on to Oracle support in an instant to help them in fault resolution.

I am quite sure that there is a mini-plateau in terms of skills with Oracle. Knowing the basic concepts gives you enough knowledge to get by day to day. But perhaps this level of skills feels high enough that correct decisions can be made. They certainly may be properly founded. But these 'foundations' are just a bit to narrow. There can be surprises and traps and this story gives excellent examples of 3 of them.

I have learned from this - thanks Doug for posting your experiences.

David P.

Oracle Certified DBA.