Import error "null value cannot be inserted in not null column" for not null columns with spaces (4311056)

When using the Import wizard, after selecting the file, and identifying the Table, the "File Preview" window will allow you to define options for "Blank Fields are Null".

Unfortunately, this is a blanket option for ALL COLUMNS. If you have a date column that is nullable, and a CHAR column that is NOT NULL but can hold spaces as a value, this import fails with error:

"null value cannot be inserted in not null column"

The wizard should recognize that empty fields are null for Nullable Culumns ONLY. If the column is defined as NOT NULL, then the attempt to populate it with null should never be done.