Block check in if occupied

[fitcrates]

Hi, 

This is my first ever app. 

Currently I am facing an issue that check in allows multiple entries in one station and shows "available" all the time while it should be not available. How do I solve this? It was working before I made a lot of changes and it all crashed and had to rebuild all structure. 

  

[scott192]

Use this as your formula instead

COUNT(
FILTER(
"Workstation Activity",
AND(
ISBLANK([Checkout]),
[Workstation] = [_THISROW].[Workstation Name]
)
)
) > 0

[scott192]

I should explain sorry...
Your original formula was asking if a list (Workstation Activity[Checkout])  is blank.  As long as there are ANY records stored in that table, then that list is NEVER going to be blank and so your AND comparison is always going to fail and your COUNT is always going to be 0.

[fitcrates]

Ok, so how to I solve this? THere is a sheet of "workstation actions". Rows include ID of the station, emai, checkin and if done then checkout. So basically it should check if there is blank checkout in the specific row containing the same ID. Don't know how to write it. 

[scott192]

You could make a slice of your workstations that are available?  Wait...I can see in your screenshot that you've already done this.  Shouldn't you be using that slice in your formula instead?

[scott192]

I think your computed key is throwing me off here.  I don't understand why you need one as you have an ID column with a uniqueid() formula.
Maybe you should explain a little bit more of what you application does and what the rules of being able to check out a workstation are?