定义常量:在sqlplus中之间输入define查看预定义的变量
SYS@itkaifang> define DEFINE _DATE = "07-MAR-17" (CHAR) DEFINE _CONNECT_IDENTIFIER = "itkaifang" (CHAR) DEFINE _USER = "SYS" (CHAR) DEFINE _PRIVILEGE = "AS SYSDBA" (CHAR) DEFINE _SQLPLUS_RELEASE = "1102000100" (CHAR) DEFINE _EDITOR = "vim" (CHAR) DEFINE _O_VERSION = "Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Produ ctionWith the Partitioning, OLAP, Data Mining and Real Application Testing options" (CHAR) DEFINE _O_RELEASE = "1102000100" (CHAR) SYS@itkaifang>
设置变量did为30,执行SQL命令时可用&引用变量did
SCOTT@itkaifang> define did=30 SCOTT@itkaifang> define DEFINE _DATE = "07-MAR-17" (CHAR) DEFINE _CONNECT_IDENTIFIER = "PROD" (CHAR) DEFINE _USER = "SYS" (CHAR) DEFINE _PRIVILEGE = "AS SYSDBA" (CHAR) DEFINE _SQLPLUS_RELEASE = "1102000100" (CHAR) DEFINE _EDITOR = "vim" (CHAR) DEFINE _O_VERSION = "Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Produ ctionWith the Partitioning, OLAP, Data Mining and Real Application Testing options" (CHAR) DEFINE _O_RELEASE = "1102000100" (CHAR) DEFINE DID = "30" (CHAR) SCOTT@itkaifang> SELECT * FROM emp WHERE deptno=&did; old 1: SELECT * FROM emp WHERE deptno=&did new 1: SELECT * FROM emp WHERE deptno=30 EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO ---------- ---------- --------- ---------- ------------------- ---------- ---------- ---------- 7499 ALLEN SALESMAN 7698 1981-02-20 00:00:00 1600 300 30 7521 WARD SALESMAN 7698 1981-02-22 00:00:00 1250 500 30 7654 MARTIN SALESMAN 7698 1981-09-28 00:00:00 1250 1400 30 7698 BLAKE MANAGER 7839 1981-05-01 00:00:00 2850 30 7844 TURNER SALESMAN 7698 1981-09-08 00:00:00 1500 0 30 7900 JAMES CLERK 7698 1981-12-03 00:00:00 950 30 6 rows selected. SCOTT@itkaifang>