语法:SUBSTR(被截取字符串,开始,结束)
例:显示所有员工姓名的前5个字符;
SCOTT@itkaifang> SELECT SUBSTR(ename,1,5) FROM emp; SUBSTR(ENAME,1,5) -------------------- SMITH ALLEN WARD JONES MARTI BLAKE CLARK SCOTT KING TURNE ADAMS JAMES FORD MILLE 14 rows selected. SCOTT@itkaifang> SELECT SUBSTR(ename,0,5) FROM emp; SUBSTR(ENAME,0,5) -------------------- SMITH ALLEN WARD JONES MARTI BLAKE CLARK SCOTT KING TURNE ADAMS JAMES FORD MILLE 14 rows selected. SCOTT@itkaifang>
例:显示员工姓名最后一个字母。
SCOTT@itkaifang> SELECT SUBSTR(ename,-1) FROM emp; SUBS ---- H N D S N E K T G R S S D R 14 rows selected. SCOTT@itkaifang>