doubts with connectivity and databases

[Anonymous]

hello the doubt that I walk frequently is the following, I am new to power bi but I joined a company like trainee they left me practically alone with power bi, and because the project is already underway I lost a lot of basic knowledge, at the beginning it was difficult but it is being a very high learning load. Going back to my doubts and the next, I got into a debate here, to find out with the best way to connect a database to the power bi, the first option: creating a super database with all the tables and then listing them , and from it create the reports, or second option: create a database for each segment such as financial report create a database only with the financial tables or create a production report and then get a database with only production information.

obs: Or if there are none of these alternatives, which one do you recommend or find the best

[lbendlin · Accepted solution]

Absolutely the first option (having a company wide, well maintained data dictionary without contradictions, and with a well staffed data stewardship team) is preferable as it avoids all the duplications and misunderstandings of the second option. 

Humans seem to have difficulty finding the time to do things right, but they will happily spend that same time trying to mend hopelessly broken things. 

[lbendlin]

Realistically the second option is unfortunately more popular, mostly because teams have different data privacy and security requirements.  Financial data subjects have very different sensitivity than internal support cases, for example. If you go for a unified company wide data mart you need to have the option for solid segmentation  (object level security) which Power BI is just about to introduce. 

You can still coordinate between the data islands so that everybody is at least aware of each other.

[Anonymous]

so as you said that unfortunately the second option is the most used. Would it be better to make the first option?

or another option better in your opinion