Lose data and dropdown list when I apply a column formula
I have a working cell formula that takes the parent value and adds it to the cell:
=IF( COUNT(PARENT()) = 0, "", PARENT() )
But when I apply this as a Column Formula, it wipes all existing cell data in the column and also restricts the ability to use the Dropdown List column type function.
I thought I could change the formula to only work if a cell is blank, like so...
=IF(ISBLANK(), IF(COUNT(PARENT()) = 0, "", PARENT()),0)
But this formula triggers an #INCORRECT ARGUMENT SET
error.
Question: How do I use the 1st formula as a column formula, without:
 wiping existing data?
 removing the ability to use the dropdown list?
 only trigger when a column cell is blank?
😵
Answers

@Dash that's how column formulas work, the cell values will be set by the formula and this renders the column uneditable. There is no way to apply a column formula selectively.
Darren Mullen, join the Smartsheet Guru Elite
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Author of: Smartsheet Architecture Solutions

@Darren Mullen answer is correct. You're going to need to find an alternative new column to do this in so you can still use your dropdown or change up tactics of how your sheet is going to accomplish what it needs to do.
Additionally, you're getting an incorrect argument set on that other formula because you didn't define where the ISBLANK is supposed to be looking to determine if it's blank or not.
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