Is there a :: in the column name? Could the column be for a field with global storage?
The fields that are visible in table view are not necessarily the same fields that you see in form view. You may need to click the modify button and check to see what fields have been selected to be visible in Table View.
If a field from a related table occurrence (you'll see tableoccurrenceName::FIeldName in the column header), it's possible that all your records match to the same record in the related table and thus the fields from that table occurrence all show the same value.
A field with global storage will also show the same value for every record.
I did, in fact! A "sample name" field was somehow from a duplicate table that I created only to have a self reference to have a portal that showed related records in the same table. Is there anything not obvious that can cause that to occur? When I originally made this table, the duplicate didn't exist, so I'm fairly certain I didn't add the field from the duplicate table. Just wondering if there's an action I can avoid in the future, or if I will disrupt anything about the self relation by fixing this.
Very helpful as always, thanks!
The only way that a field can appear in a table view is if either a) it was placed on the layout while in layout mode or b) it was selected after clicking Modify.
You might have a preference set in preferences that automatically adds new fields to the current layout and that might have slipped a field onto your layout that you didn't realize that you had.