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IBM Cognos 8 Platform => COGNOS 8 => Framework Manager => Topic started by: laks on 18 Aug 2010 12:31:23 PM

Title: Limit on number of databases?
Post by: laks on 18 Aug 2010 12:31:23 PM
Hi Folks,

I would like to know is there any limit on number of databases a FM Model can connect. We have a new requirement to get data from over 200 MySQL databases ::) (very small databases).

As there are very small if possible we want to avoid ETL.

Thanks
Title: Re: Limit on number of databases?
Post by: dlafrance on 18 Aug 2010 02:44:58 PM
i don't think there is a maximum of datasource, but you will have a lot of "fun" doing queries to join or union all the possible datasource.

It will be hard to maintain also, on developper side to have a lot of datasource..
Title: Re: Limit on number of databases?
Post by: laks on 19 Aug 2010 12:22:31 PM
thanks  :)
Title: Re: Limit on number of databases?
Post by: cognostechie on 19 Aug 2010 01:41:56 PM
Just sharing ..

In case , the schema structures are the same and the only difference is the data, you can use a Prompt to select the Database when you run the report. That way, you can avoid the joins and unions.

We had a situation where the customer had 30 schemas and the only difference was the data, not the structure of the schema.
Title: Re: Limit on number of databases?
Post by: laks on 26 Aug 2010 12:54:41 AM
Intersting  :o...

Thanks for sharing.

So is the prompting handled at FM level or at data connection level?  ::)
Title: Re: Limit on number of databases?
Post by: blom0344 on 26 Aug 2010 03:16:30 AM
In Cognos connection you can assign 1 or more connections for each datasource (we often have 10 defined). When you run a report you will automatically be prompted if the datasource has more then 1 connection defined. Each connection point to a different database (as long as database structures are identical, this will work)
Title: Re: Limit on number of databases?
Post by: laks on 26 Aug 2010 11:17:18 AM
Cool.. Thanks a lot..