How to enforce to input value from another column?

Question

I've created 3 columns:

1. Choice:
   • Banana
   • Apple
   • Orange

2.Start date

3.End date

If you select "banana", then he/she must input value for "start date" and "end date".

I tried to input the formula below at start date but it doesn't work.

=if([Choice]="Banana",[Start date]=today(),true, false)

Could anyone out there help me?

Answer 1

Try below formula:

=IF([Choice]="Banana",IF(OR(ISBLANK([Start date]),ISBLANK(End date)),false,true),true)

This satisfy the condition: If [Choice] is equal to "Banana" then user cannot leave Start date or End date columns blank.

Note:

1. Sometimes comma(,) does not work in formula (I am not sure but it is based on something language or regional settings on your site). So in that case use semicolon(;) instead of comma(,).

official documentations:

1. Calculated Field Formulas.
2. IF function.

Answer 2

You could use formula as Ganesh said via List settings->Validation settings->type the formula as below:

=IF([Choice]="Banana",IF(OR(ISBLANK([Start date]),ISBLANK(End date)),false,true),true)

Since the single column validate cannot refer to other column value, we cannot add the formula under certain column.