如何增加数据库最大连结数？

gloria

Thank you waterworld.

I tried in SQL/PLU. First I logined as userA and then in userA's session I logined as userB. From v$session, I first saw userA as a record in it, then it changed to userB, and the result of "count(*) from v$session" is the same.

I don't know if what you say can be taken as in UNIX system, when I login as UserA, I use "su - userB" to change to UserB, after finished what I want to do as UserB, I can use exit to return to UserA. But in Oracle system, I don't know how to see the same scene.

Can you please tell me how I can validate what you said?

chao_ping

from metalink,
u can select distinct type from v$session , and background, user, recursive.

Several types of sessions are reported in the V$SESSION view
of Oracle.  The Oracle background processes will create a  
minimum of five sessions -- more depending upon the  
settings for DB_WRITERS, the checkpoint process, archiving,
etc.  Each user logged into the database will create at least
one session for the initial login, and may have one or more
recursive sessions too.  Recursive sessions occur on
certian operations initiated by a user login and will add
another row to V$SESSION for that user.  It is often useful
(or necessary) to determine how many sessions for a given
user are actual logins and how many are recursive.

The TYPE column of V$SESSION can be used to determine how
many sessions are created by background processes, how many
by users and how many by recursive sessions.  it should
contain one of three values: BACKGROUND, USER, and
RECURSIVE.
但是不知道recursive session产生的具体例子。

gloria

Thank you Chao_ping very much!