Single-Ampersand Substitution Variable

Use an ampersand (&) to identify each variable in your SQL statement. You do not need to define the value of each variable.

The examples below create an iSQL*Plus substitution variable for an employee number. When the statement is executed, iSQL*Plus prompts the user for an employee number and then displays the    EMPNO, ENAME, SAL and DEPTNO for that employee.

With the single ampersand, the user is prompted every time the command is executed. See examples:

SQL> select empno,ename,sal,deptno from emp where empno=&emp_no;

Enter value for emp_no: 1234

old   2: from emp where empno=&emp_no

new   2: from emp where empno=1234

no rows selected

select empno,ename,sal,deptno from emp where empno=&emp_no;

Enter value for emp_no: 7369

old   2: from emp where empno=&emp_no

new   2: from emp where empno=7369

    EMPNO ENAME            SAL    DEPTNO

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

     7369 SMITH            800        20