oracle-databaseora-00918

Oracle UNION different columns

I have two tables looking something like:

TABLE_1
COL_A (int), COL_B (float), COL_C (float)


TABLE_2
COL_A (int), COL_B (float)

My query is using a UNION to put the results of these tables together, but where TABLE_2 doesn't have a COL_C, I'm looking to put something like '0'. But I just get a 'ORA-00918: column ambiguously defined' error

How can I get around this?

Solution

  • You can try this

    SELECT COL_A, COL_B, COL_C FROM Table1
UNION
SELECT COL_A, COL_B, 0 As COL_C FROM Table2