Oracle PL/SQL/PL SQL/Define

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DEFINE command with no arguments: list all variables defined

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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>

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Define variable

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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>

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The DEFINE command can be used to create substitution variables and assign them values

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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>

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