SQL内置函数的使用方法及结果(10)

58.USER

返回当前用户的名字

SQL> select user from dual;

USER

------------------------------

GAO

59.USEREVN

返回当前用户环境的信息,opt可以是:

ENTRYID,SESSIONID,TERMINAL,ISDBA,LABLE,LANGUAGE,CLIENT_INFO,LANG,VSIZE

ISDBA 查看当前用户是否是DBA如果是则返回true

SQL> select userenv("isdba") from dual;

USEREN

------

FALSE

SQL> select userenv("isdba") from dual;

USEREN

------

TRUE

SESSION

返回会话标志

SQL> select userenv("sessionid") from dual;

USERENV("SESSIONID")

--------------------

152

ENTRYID

返回会话人口标志

SQL> select userenv("entryid") from dual;

USERENV("ENTRYID")

------------------

0

INSTANCE

返回当前INSTANCE的标志

SQL> select userenv("instance") from dual;

USERENV("INSTANCE")

-------------------

1

LANGUAGE

返回当前环境变量

SQL> select userenv("language") from dual;

USERENV("LANGUAGE")

----------------------------------------------------

SIMPLIFIED CHINESE_CHINA.ZHS16GBK

LANG

返回当前环境的语言的缩写

SQL> select userenv("lang") from dual;

USERENV("LANG")

----------------------------------------------------

ZHS

TERMINAL

返回用户的终端或机器的标志

SQL> select userenv("terminal") from dual;

USERENV("TERMINA

----------------

GAO

VSIZE(X)

返回X的大小(字节)数

SQL> select vsize(user),user from dual;

VSIZE(USER) USER

----------- ------------------------------

6 SYSTEM