Calculate the difference between two custom fields

[Dave Jones]

I am attempting to calculate the difference between two custom fields (in days) and populate the result into a number field. 

See screenshot below for what I have entered.

I get an error message which states "Additional fields contains invalid field(s) in 'update' or 'fields' section: Custom Field Name" but this does not tell me at all where the issue is. I have tried various variations but get no where.

Thanks for your help.

[Stephen Wright _Elabor8_ · Accepted solution]

Hi @Dave Jones 

I recreated this, using the Start Date and End Date fields, and using this smart value:

{{issue.customfield_10123.diff(issue.customfield_10456).days}}

^ And it worked as expected.

What does the rest of your rule look like? Are these both Date Picker fields?

Ste

[Dave Jones]

Thank you for your quick response. I have tried the same as you entered but it still does not work for me:

Below are the screenshots of the custom fields so you can see their IDs:

Here is the rest of the rule, but there does not seem to be anything unusual? I should explain I am very new to this so I am probably missing something basic.

[Alex Koxaras _Relational_ · Accepted solution]

Hi @Dave Jones and welcome to the community,

Are these two custom field date fields? From the looks of it, the second field, to which you have append the suffix .value, isn't a date field. So I'm not sure you can calculate the difference in days.

[Dave Jones]

Hello Alex. I have posted screenshots of both custom fields above. They are both Date fields. I have tried without the value suffix and it still does not work.

[Alex Koxaras _Relational_]

@Dave Jones close the additional fields (JSON) which you have opened ("more options").

[Dave Jones]

:) Thank you. That was it.