Concat rows into single column
Imran> select * from student; Sno ---------- 1 2 3 Imran> select xmlagg (xmlelement (e,Sno ||',')).EXTRACT('//text()') as Sno from (select distinct Sno from student); Sno -------------------------------------------------------------------------------------------------------------------------- 1,2,3, If we observe the above result it contains comma(,) at the end. In order to remove comma(,) we will use RTRIM function: Imran> select rtrim(xmlagg (xmlelement (e,Sno ||',')).EXTRACT('//text()'), ',') as Sno from (select distinct Sno from student); Sno ------------------------------------------------------------------------------------------------------------------------- 1 ,2,3