Selecting from different rows

Question

Hi all,
The database is Oracle10g.
I want to select one column from one row of a table, based on a condition, and the second column of the second row of that first row of the same table.
There should be an order by clause to enable it so that I can talk about first row and second row.
For example : select ename , job from emp where deptno = 20; . And here the column ename is for the first employee of deptno 20 , and job is the column for the second employee in the same deptno.
How to achieve this ?
Thank you very much indeed

Answer 1

I think you want this.
SQL> create table test as select rownum id,'ROW '||rownum r from all_objects where rownum<=5;
Table created.
SQL> select * from test order by id;
        ID R
         1 ROW 1
         2 ROW 2
         3 ROW 3
         4 ROW 4
         5 ROW 5
SQL> select id,r,lead(r,1) over (order by id) next_r from test order by id;
        ID R          NEXT_R
         1 ROW 1      ROW 2
         2 ROW 2      ROW 3
         3 ROW 3      ROW 4
         4 ROW 4      ROW 5
         5 ROW 5The feature you are looking for is analytic functions. You can read about them here: http://download.oracle.com/docs/cd/B19306_01/server.102/b14223/analysis.htm#sthref1684