Why do some MDA objects allow for Create Formula option while other objects only have preset options when trying to add a Calculated Field?

Manmeet - Email logs is actually a Gainsight system object so does have some restrictions on what fields you can add.  You can add these to your Monthly Aggregation object since it is your own custom object.  With that said, we are looking at adding flexibility to some of these kind of objects.  

If this is more pressing for you, you do have the option to "copy" using Rules the data in your Email Logs to a custom object in MDA (you can set up the object using Data Management and then use rules to populate it).  Using this, you would then have ability to Create Formula as you see on other custom objects.

Thank you for that explanation! That makes sense, I wasn't sure since I wasn't here when Gainsight was first onboarded and the MDA set up.

I was wondering then, if you could help me with the use case. I am just trying to get a field into that Email Logs object that will count the "Unopened" emails from Outreach. I figured since I have the "Sent" and the "Opened", I could at least get a rough estimate by doing a calculated field of ('Sent' - 'Opened'). 

Would this be better accomplished using the Rules Engine and building a calculated field that is then loaded to the Email Logs object? I have looked over the Calculated Fields documentation on the support page and wasn't completely sure how to set it up so that it sums 'Unopened' emails. 

To add on to this, would this also be the reason why a created field in the "Email Logs" MDA object would not show up in the Rules Engine - 'Permissions - Rule Load Actions' under the "Available Fields" section? 

If I could get this new custom field (from the Email Logs MDA) in here, I could push a rule I have created that would load my custom calculated field (from the Rules Engine) into the Email Logs MDA. 

Hi Manmeet,

You can use the "Expression" in Transformation task of a Bionic rule to calculate "unopened emails" (sent - opened) and then load into a field of an MDA object. You do not need to create a calculated field in the source.

Regards,
Jitin