Remove redundant Access field cells

问题:

Continued from Combine Access fields into one field given two queries

I have the table below with three main fields Name_2010, Name_2011 and Name_2012 and they need to be integrated as Name_Final.

I used the query below to select only a particular member of the three fields per row but currently it does not work as intended as it does not recognize redundant cells.

SELECT
  IIf(Name_2010 In (Name_2011, Name_2012), '', Name_2010) 
  AS N1,
  IIf(Name_2011 In (Name_2010, Name_2012), '', Name_2011) 
  AS N2,
  IIf(Name_2012 In (Name_2010, Name_2011), '', Name_2012) 
  AS N3
  FROM Table1;

What query should I use to achieve Name_Final given my current table?

回答1:

SELECT ID, N1 &
  IIf(N2 <> N1, N2, '') &
  IIf((N3 <> N2) And (N3 <> N1), N3, '') AS Name_Final
FROM
  (SELECT ID, Nz(Name_2010) AS N1, Nz(Name_2011) AS N2, Nz(Name_2012) AS N3
   FROM Table1) AS T
ORDER BY ID;

The ORDER BY clause is for what it says, rather than being a part of the 'Name_Final' calculation.