Compare Start Date value with End date list

[Mic_L_Angelo]

Hello folks.

I’d like some assistance with writing an expression i feel dumb asking about.

Long story short, I got a “Vacation” table, for when people are on PTO vacation.

It has 2 columns,
“Start Date” ( the date the person begins vacation)
“End Date” ( the date the person ends vacation)

Simply put, I don’t want people to make a new entry if the Start Date is before an End Date already in the table. (They shouldn’t make a new vacation record if it’s within the time span of a previous one)

So I need a ValidIf formula that says “this row’s Start Date is greater than all this table’s End Dates”

I wrote the following formula,

[_THISROW].[Start Date] > [End Date]

but it always returns false, even when the new Start Date is greater than all End Dates.

I can’t figure out the problem solution. Does anyone have any insight?

[Steve · Accepted solution]

Your expression:

[_THISROW].[Start Date] > [End Date]

Compares the Start Date column value of the row with the End Date column value of the same row.

Given this:

Mic_L_Angelo:

I don’t want people to make a new entry if the Start Date is before an End Date already in the table.

It seems like you want:

([Start Date] > MAX(Vacation[End Date]))

See also:

help.appsheet.com

MAX()

Highest item in list

help.appsheet.com

List Expressions and Aggregates

List expressions use operators that result in a list or numeric value.

help.appsheet.com

Valid_If Column Constraint

How to check if a given form input is valid based on its type.

[Mic_L_Angelo]

Steve:

([Start Date] > MAX(Vacation[End Date]))

Yes! that was i was looking for. Agh, I knew it was a dumb question. Many thanks for the swift response, Steve!