You are using the terms 'record' and 'field' backwards.
A record has fields, therefore you would have 'longest field in a record.
If you table had the following fields - Name, Type, and Agerotia you would
use a union query like this first --
SELECT "Name" AS [Field], Len([Name]) AS [Size]
FROM YourTable
UNION ALL SELECT "Type" AS [Field], Len([Type]) AS [Size]
FROM YourTable
UNION ALL SELECT "Agerotia" AS [Field], Len([Agerotia]) AS [Size]
FROM YourTable;
Run it and then click on the Z-A sort.