---取1到3位
SQL> select job,substr(job,1,3) from emp;
JOB SUBSTR
--------- ------
CLERK CLE
SALESMAN SAL
SALESMAN SAL
MANAGER MAN
SALESMAN SAL
MANAGER MAN
MANAGER MAN
ANALYST ANA
PRESIDENT PRE
SALESMAN SAL
CLERK CLE
JOB SUBSTR
--------- ------
CLERK CLE
ANALYST ANA
CLERK CLE
14 rows selected.
---取后2位
SQL> select job,substr(job,length(job)-1,length(job)) from emp;
JOB SUBSTR(JOB,LENGTH(
--------- ------------------
CLERK RK
SALESMAN AN
SALESMAN AN
MANAGER ER
SALESMAN AN
MANAGER ER
MANAGER ER
ANALYST ST
PRESIDENT NT
SALESMAN AN
CLERK RK
JOB SUBSTR(JOB,LENGTH(
--------- ------------------
CLERK RK
ANALYST ST
CLERK RK
14 rows selected.