Hbase mapred classes question

[Lars George]

Hi,

I have two questions for the mapred BuildTableIndex classes folks.
First, if I have 40 servers with about 32 regions per server, what would 
I set the mapper and reducers to?

And secondly, is it allowed to add new column values during the process? 
For example, if I read all rows and the column "contents:A" (for example 
row123.contents:A), analyze the data and then write out the result in 
"row123.contents:B", is that OK to do?

Thanks,
Lars

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Lars George, CTO
WorldLingo