I think many users use Excel to keep their data because not everyone in the organization has the access to the company database.
I observed that, the date did not import correctly if there is missing data in between rows in the date column (does it that mean JMP cannot handle text and numeric value in the same column?).
To recap few discussions about date format return to 01/01/1904 after Excel import (Import from Excel -Date as Character issue):
1) https://community.jmp.com/t5/Discussions/Need-help-converting-a-date-format-from-character-to-numeric-in/m-p/356131#M60603
2) https://community.jmp.com/t5/Discussions/probl%C3%A8me-importation-date-%C3%A0-partir-d-excel/m-p/601264#M80458
Example:
I want to convert to convert numeric 45008.078125 (JMP numerical value after import from Excel) to 3/23/2023 1:52:30 AM (as per actual data in Excel)
Initial solution that I received from JMP is to install add-in which can be found at below link;
https://community.jmp.com/t5/JMP-Add-Ins/Data-Table-Tools-Add-in/tac-p/653491#M1772
(However, the add-in cannot be used for this case, so it was suggested to use date formula & I need to edit the formula with minus 2days to get the correct date)
Steps:
1) Format the Date column from Character to Numeric
2) Create new Column formula as below;
As Date( In Days( :Diebond End Date JMPImport) + Informat ("1/1/1900", "<MM><D><YYYY><HH><:><MM><:><SS><AMPM>")) - In Days( 2 )</AMPM></SS></MM></HH></YYYY></D></MM>
The JMP formula suppose to use 01/Jan/1900 but somehow it exceed by 2 days. Why is that so?
3) Set the format pattern to the desirable format
I set format pattern: <:><:>
Example of JMP file in the attachment (5 empty cells in Diebond End Date Excel)
I'm using JMP 17.0.0.
Not sure if JMP 17.1 has resolved this issue.
