Question

I have 2 tables like which I would like to query to form a new table.

table 1

 number    type serial index 1000001     613      3     1 1000001     613      3     1 1000001     613      3     1 1000001     613      3     1 1000001     613      4     1 1000001     613      3     1 

table 2

 number    type serial index 1000001     613      3     2 1000001     613      3     3 1000001     613      3     4 1000001     613      3     4 1000001     613      4     2 1000001     613      3     1 

I am looking for a query which gives a resultant of indexes and numbers like this, and adds the index, and gives the result:

output table   number  index 1000001      3 1000001      4  1000001      5  1000001      5  1000001      3 1000001      2  

I want to prevent cross joins here. I can’t use where clause because the numbers are same in both tables only the index varies. How can I execute this one-to-one and not one-to-many.

Answer 1

I don’t think it’s possible to do what you are asking. You would have to be able to distinguish each row uniquely to guarantee a 1-to-1 result (this is normally the job of your index column or ID column).

You might be able to jerry-rig something with rownum, however, if the tables are identically ordered, then perhaps you’ve over-normalised. Table 1 and 2 should really just be one, and you have two index columns (index1 and index2) in the one table.