8120 A field is null.
A field which is defined as "NOT NULL" or a field which is involved in an index was passed as a NULL value to Tbl_Select or TblMvFld was asked to move data FROM the row returned by Tbl_Select and the field containing the data was null.
This is an internal error which should be handled by other procedures. It should not cause a restart or be reported to users.
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