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Home -> Community -> Mailing Lists -> Oracle-L -> Re: System TS size
100 GB data warehouse, is that the raw data or the
total disk space you think you will have ?
The system tablespace is never a big one, in fact its size depend a lot on the version of Oracle you're using. Between 200 and 300 megs.
In the other hands the temp tablespace in a
datawarehouse is a big one.
Will your fact tables be partitionned ?
Do you have a lot of aggregates ?
Will you grind a lot of data ?
Around 1.5 time the largest table is a good start.
For the rollback segment, it depends on how much data you will load .
In your case, the sort_area_size will be less important than hash_area_size. I increased the hash_area_size to a very large value (that was 2 years ago, around 300-400 M I think) in the sql scripts doing the aggegates.
The SGA size will vary according to your needs. Will there be a lot of users querying the warehouse or will the data be loaded in desktop olap tool,.... there are a lot of configurations. It depens on what you do.
I recommend the Oracle 8 and 8i books on datawarehousing by Gary Dodge and Tim Gorman.
HTH