Create a summary field totaling the number of separate days represented by child records with date fields

I have a solution if there are a reasonable number of days per parent. What is the reasonable maximum number of days per Parent?

Hmm, how about 10 days max.

Ok, here we go. This will work, it�s native and you can set it up in 15 minutes.


One Service has Many Time Entries.

Create a Summary field of the Minimum Date. Call it [Service Date 1]

Lookup [Service Date 1] down to Time Entries.


Because we are lazy, Duplicate the Summary field but this time add a filter [Date] > [Service Date 1], and call it [Service Date 2]


Lookup [Service Date 2] down to Time Entries.


Because we are lazy, Duplicate the [Service Date 2] Summary field to similarly make [Service Date 3]


So let�s say you now have 10 of them. Some will be null if there�s less than 10 unique dates.


So the final answer is the number of non null dates.


Count(

not isnull([Service Date 1]),

not isnull([Service Date 2]),

not isnull([Service Date 3]),

Etc

not isnull([Service Date 10]))

Oh that is elegant Mark. One minor change I made to the final summary field using Count:

Count( [Service Date 1], 
[Service Date 2], 
[Service Date 3], 
...
[Service Date 10]
)

Works great!

Right! There was no need for the not IsNull at all.