Join columns side by side in result set [closed] - sql

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Closed 10 years ago.
I would like my result to look something like this
FirstName1 LastName1 FirstName2 LastName2
Amy Smith Bob Stone
Fred Joker Gina White
Where FirstName1 and FirstName2 have same data types but nothing I can use to join (assume no one has same names) and the same goes for LastName1 and LastName2.
I tried to create 2 tables. First table contains FirstName1 and LastName1. Second table contains Firstname2 and LastName2.
Then I use
SELECT table1.FirstName1, table1.LastName1, table2.FirstName2, table2.LastName2
FROM table1, table2;
But this gives me a lot of duplicates. Any suggestions?

Answer 1

SELECT t1.FirstName1, t1.LastName1, t2.FirstName2, t2.LastName2
FROM
(SELECT
FirstName1,
LastName1,
ROW_NUMBER() OVER (ORDER BY FirstName1) 'RowNumber'
FROM table1
) AS t1
FULL OUTER JOIN
(SELECT
FirstName2,
LastName2,
ROW_NUMBER() OVER (ORDER BY FirstName2) 'RowNumber'
FROM table2
) AS t2
ON t1.RowNumber = t2.RowNumber
FULL OUTER JOIN will handle the cases where the number of rows from the two tables are not the same.

Answer 2

You should never do what you're trying to do, but try to use DISTINCT
SELECT Distinct
table1.FirstName1,
table1.LastName1,
table2.FirstName2,
table2.LastName2
FROM table1, table2;
The problem with your approach is that the retrieved dataset doesn't make any sense. Why do you want to do it like this anyways?
Edit: you can always do this do this:
select table1.FirstName1, table1.LastName1, table2.FirstName2, table2.LastName2
from table1, table2
where table1.rownum= table2.rownum;

Answer 3

"Oh haha I am really just trying to make it looks pretty. I am used to
programming in C and Java where all kinds of output are pretty
possible. "
Database programming is different. In this realm content is more important than mere prettiness. So when it comes to result sets the database insists that all the columns in a row share a meaningful relationship (the clue is in the name, relational database).
Your problem is, you have no tables with no key in common and hence no way to join the two sets of rows together. Without a proper WHERE clause the database implements a cross join, i.e. a cartesian product, and that's where all the duplication comes from.
Given that you don't have meaningful keys your only option is to fake them; the approach shown by Vikdor is one way to achieve this.