Oracle PL/SQL/PL SQL/Define
DEFINE command with no arguments: list all variables defined
SQL>
SQL> -- DEFINE command and specifying no arguments: list all variables defined
SQL>
SQL> DEFINE V_STUDENT_NBR = "1000";
SQL>
SQL> DEFINE
DEFINE _DATE = "10-SEP-06" (CHAR)
DEFINE _CONNECT_IDENTIFIER = "XE" (CHAR)
DEFINE _USER = "sqle" (CHAR)
DEFINE _PRIVILEGE = "" (CHAR)
DEFINE _SQLPLUS_RELEASE = "1002000100" (CHAR)
DEFINE _EDITOR = "Notepad" (CHAR)
DEFINE _O_VERSION = "Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production" (CHAR)
DEFINE _O_RELEASE = "1002000100" (CHAR)
DEFINE _RC = "0" (CHAR)
DEFINE V_STUDENT_NBR = "1000" (CHAR)
SQL>
SQL>
SQL>
Define variable
SQL>
SQL> -- examine the contents of a variable created using the DEFINE command by typing DEFINE
SQL> -- and specifying the variable name:
SQL>
SQL> DEFINE V_STUDENT_NBR = "1000";
SQL>
SQL> DEFINE v_student_nbr;
DEFINE V_STUDENT_NBR = "1000" (CHAR)
SQL>
SQL> DEFINE V_STUDENT_NBR = "1000" (CHAR);
SQL>
SQL>
The DEFINE command can be used to create substitution variables and assign them values
SQL>
SQL> CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
2 ENAME VARCHAR2(10),
3 JOB VARCHAR2(9),
4 MGR NUMBER(4),
5 HIREDATE DATE,
6 SAL NUMBER(7, 2),
7 COMM NUMBER(7, 2),
8 DEPTNO NUMBER(2));
Table created.
SQL>
SQL> INSERT INTO EMP VALUES (7369, "SMITH", "CLERK", 7902, TO_DATE("17-DEC-1980", "DD-MON-YYYY"), 800, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7499, "ALLEN", "SALESMAN", 7698, TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7521, "WARD", "SALESMAN", 7698, TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7566, "JONES", "MANAGER", 7839, TO_DATE("2-APR-1981", "DD-MON-YYYY"), 2975, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7654, "MARTIN", "SALESMAN", 7698,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7698, "BLAKE", "MANAGER", 7839,TO_DATE("1-MAY-1981", "DD-MON-YYYY"), 2850, NULL, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7782, "CLARK", "MANAGER", 7839,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10);
1 row created.
SQL> INSERT INTO EMP VALUES (7788, "SCOTT", "ANALYST", 7566,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7839, "KING", "PRESIDENT", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10);
1 row created.
SQL> INSERT INTO EMP VALUES (7844, "TURNER", "SALESMAN", 7698,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7876, "ADAMS", "CLERK", 7788,TO_DATE("12-JAN-1983", "DD-MON-YYYY"), 1100, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7900, "JAMES", "CLERK", 7698,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 950, NULL, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7902, "FORD", "ANALYST", 7566,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 3000, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7934, "MILLER", "CLERK", 7782,TO_DATE("23-JAN-1982", "DD-MON-YYYY"), 1300, NULL, 10);
1 row created.
SQL>
SQL>
SQL> -- DEFINE
SQL>
SQL> -- The DEFINE command can be used to create substitution variables and assign them values.
SQL>
SQL> -- Any variable created with the DEFINE command stays in memory until you exit the SQL*Plus session
SQL> -- or until you delete the variable using the UNDEFINE command.
SQL>
SQL> -- The DEFINE command is limited in that it can be used only to create variables of datatype
SQL> -- CHAR
SQL>
SQL> DEFINE EmployeeID=7902;
SQL>
SQL> SELECT *
2 FROM Emp
3 WHERE empno = &EmployeeID;
old 3: WHERE empno = &EmployeeID
new 3: WHERE empno = 7902
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- ---------- --------- ---------- --------- ---------- ---------- ----------
7902 FORD ANALYST 7566 03-DEC-81 3000 20
SQL>
SQL> drop table emp;
Table dropped.
SQL>
SQL>
SQL>