Help: 8i merge/upsert/insert/update one table from another.

Note: I am a beginner. We currently use Oracle 8i at work.

I am trying to update table REG with the data from table REGTEMP. I have tried a few methods that I found while searching the internet to no avail. I believe it may be in part to a few issues. 1) both tables have the same layout. Columns are named the same and same type.
2) the first 5 columns are used to create the primary key.

I am running in a Oracle 8i environment so it appears the merge command is not available.

Here is the last thing I tried:

UPDATE (SELECT REG.*, REGTEMP.* FROM REG, REGTEMP

     WHERE REG.COL1 = REGTEMP.COL1,
          AND REG.COL2 = REGTEMP.COL2,
          AND REG.COL3 = REGTEMP.COL3,
          AND REG.COL4 = REGTEMP.COL4,
          AND REG.COL5 = REGTEMP.COL5)
     SET COL6 = COL6_1,
          COL7 = COL7_1,
          COL8 = COL8_1,
          COL9 = COL9_1;

INSERT INTO REG (SELECT * FROM REGTEMP WHERE NOT IN (SELECT REGTEMP.* FROM REG, REGTEMP

     WHERE REG.COL1 = REGTEMP.COL1,
          AND REG.COL2 = REGTEMP.COL2,
          AND REG.COL3 = REGTEMP.COL3,
          AND REG.COL4 = REGTEMP.COL4,
          AND REG.COL5 = REGTEMP.COL5);

The update give me this error:
ORA-01779 cannot modify a column which maps to a non key-preserved table.

Please note. I do not mind ditching the code used above. I believe there are easier ways of doing this. Also I would like to know the correct method to approach this task. I am open to any suggestions.

Thank you for your time,

Eric Received on Wed Mar 21 2007 - 07:34:36 CDT