Oracle数据库怎么查询连接当前用户的所有计算机的名称或IP

  Oracle中通过v$session表中的OSUSER和MACHINE字段可以查看当前客户端登陆连接的“ *** 作系统名称”和“机器名”，但没能查看到客户端电脑IP。

查询：

select  from v$session where username='HFY120401';

你先自己去看下 substr 好instr 两个的用法。
实现你说的方法可以：
select SUBSTR('21806182', 1,length('21806182') - instr('', reverse('21806182')))
from (select
from T_Base_IPAddressInfo
where '21806182' between startip and endip) t
where startip =
SUBSTR('21806182', 1,length('21806182') - instr('', reverse('21806182'))) ||
SUBSTR(startip, instr('', reverse(startip)))

select startip,endip,location from T_Base_IPAddressInfo where cint(replace(ip,"",""))>= cint(replace(startip,"","")) and cint(repalce(ip,"","") <= cint(replace(endip,"",""))

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