UNION ALL query: “Too Many Fields Defined”

Question

I\'m trying to get a UNION of 3 tables, each of which have 97 fields. I\'ve tried the following:

select * from table1
union all
select * from table2
union a         


        

Answer 1

I had two tables with 173 fields each (2 x 173 > 255!). So I had to resort to splitting the tables in half (keeping the primary key in both), before using the UNION statement and reassembling the resulting output tables using a JOIN.

    select u1.*, u2.* 
    from (
      select [field1_PKID],[field2],...,[field110] 
      from table1

      union all

      select [field1_PKID],[field2],...,[field110] 
      from table2
      ) as u1
    inner join (
      select [field1_PKID],[field111],...,[field173] 
      from table1

      union all 

      select [field1_PKID],[field111],...,[field173] 
      from table2
      ) as u2
    on [u1].[field1_PKID] = [u2].[field2_PKID]