Full source flow of view definition

Hi,
I am new to opengamma. I am trying to find out the calculation results show in Analytics UI page.
Here I am summarized what I am really expecting,

  1. I have example simulated version source, By using this
    i) i have created one portfolio with one positions of EQUITY 5000.
    ii) I have added the portfolio into view definition in Configure UI page with column CAMP Beta. i didnt give any other constraints.
    iii) I have tried to see the portfolio in Analytics UI page. The portfolio has been displayed with some calculated values. I dont know how this value has calculated.

Could you please explain the source flow of this view definition?

How the functions are called?
Why it is limited to only four functions?