title: combining and joining two tables with different no. of columns and same column name
body: <p>I tried to combined tables which is <strong>fus_shift and root table</strong> into a new table which is <strong>final table</strong> but it outputs like "<strong>ERROR at line 2:
  ORA-01789: query block has incorrect number of result columns</strong>". I tried also joining table as my alternative but it also outputs "<strong>ERROR at line 3:  ORA-00918: column ambiguously defined</strong>". Is there another way to do combining and joining two table with different number of columns and having the same column name respectively? Thanks again:-)<br><br>
  code error:<br>
  create table final as<br>
  select * from fus_shift<br>
  union<br>
  select * from root;<br></p>
  
  <p>code error:<br>
  select record_num,test_num,t_date,t_time,system_type,category,comments,val<br>
  from fus_shiftrpt,root<br>
  where record_num=record_num;<br><br></p>
  
  <p>my tables:<br><br></p>
  
  <pre><code>                                 fus_shift Table
  
  
             Record_Num       test          date      time         system   
             -----------------------------------------------------------
                  1          test15      08-11-12  13:20:01    sys23 
                  2          test17      08-11-03  14:24:00    sys24
                  3          test13      08-11-13  17:25:04    sys45
                  4          test15      08-11-14  18:24:00    sys67
                  5          test16      08-11-15  19:24:06    sys45
  
  
                                   root Table
  
             Record_Num      category   comments    validated by
             ---------------------------------------------------
                    1        dirt        checked        admin
                    2        prog        checked        admin
                    3        dirt        checked        pe
                    4        wires       checked        ee
                    5        prog        repair         admin
  </code></pre>
  
  <p><em>emphasized text</em></p>