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Jyosi jyosiJyosi jyosi 

Formula fields for master detail relationship

Hello Everyone

We have contact and custom object on the custom object we have a picklist field state.
whenever the pick list value on custom object is CT i need to check the box to true on contact detail page 
I wrote the formula but is not working.

The formala has been written on Contact object


Can any one help me out where i am going wrong.

Venkat PolisettiVenkat Polisetti

You can only pull values to children from the Parent, but not the other way.

Contact --> Parent
State Registration --> Child of Contact

You can pull a value from Contact (Parent) on to its related object, State Registration (child), but not the other way round. If the relationship is Master Detail, then you can create a Roll-up summary field on the Contact to pull summary information from State Registration such as a count of  CT residents.

Hope this helps.
Geoffrey J FlynnGeoffrey J Flynn
Hi Jyosi,

The issue here is that you can have many instances of the detail object for each Contact(master) record, so you can't have it conditional on a single entry.  You could look at a cross-object workflow rule to see if this can somehow work
A master-detail is a one to many relationship by definition, so you should revisit your data model here if this is something you are trying to achieve.  There are solutions out there, but they often involve triggers if you can't get a cross-object workflow to work, and can't use a roll-up.  In this case I don't see how it fits.