Concatenation Operator

SQL CONCATENATION

You can use concatenation to link columns to  another columns ,when you concatenate -oracle concat-tow columns . output displays as a single column .

For Example

SELECT EMPNO||' '||ENAME

FROM EMP;

EMPNO||''||ENAME

------------------

7369 SMITH

7499 ALLEN

7521 WARD

7566 JONES

7654 MARTIN

7698 BLAKE

7782 CLARK

7788 SCOTT

7839 KING

7844 TURNER

7876 ADAMS

Also You can use allies

Select empno||' '||ename as employee

From emp;

EMPLOYEE

---------------

7369 SMITH

7499 ALLEN

7521 WARD

7566 JONES

7654 MARTIN

7698 BLAKE

7782 CLARK

7788 SCOTT

7839 KING

7844 TURNER

7876 ADAMS