Very Large Databases

Hello,

I have a couple of what I hope are simple questions. I am currently working on the feasibility of migrating several Databases' into 1 large DB. I am also considering using RAW devices instead of formatted filesystems (We currently use Digital UNIX 40F).

My questions are:

1. Is there a limit to the number of datafiles that Oracle can address. I intend to resize datafiles on the fly instead of adding additional datafiles but I still need to know if there are any limitations. I have checked the init<SID>.ora file and the only likely offender is db_files. Does this have any effect on the number of datafiles allowed? If so, can I change this parameter on the fly or will I have to recreate the control files?
2. Is there a limit to the size of individual datafiles. If this project goes ahead, we are likely to see datafiles as big 30GB - 100GB!
3. Are there any limitations to the size of raw disk that Oracle can address.
4. Are there any good Oracle web sites that you cyberspace people recommend?

Any help would be very much appreciated.

Thanks,

Phil.

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Phillip Adams