Oracle View and modify the maximum number of connections

First step, on the cmd command line, enter sqlplus or Open command window directly in Plsql

Step two, follow the prompts to enter the user name and password

1. View processes and Sessions parameters

Sql> Show parameter Processes NAME                                 TYPE        VALUE db_writer_processes                 integer    1 gcs_server_processes<　　C9/>integer    0 job_queue_processes                 integer    log_archive_max_processes           integer    2 Processes                           Integer    50

Sql> Show parameter Sessions NAME                                 TYPE        VALUE license_max_sessions                integer    0 license_sessions_ Warning            integer    0 logmnr_max_persistent_sessions      integer    1 sessions                            integer    shared_ Server_sessions              Integer

　 2. Modifying processes and Sessions values 　　

Sql> alter system set PROCESSES=300 Scope=spfile;　　The system has changed.　　Sql> alter system set sessions=335 Scope=spfile; The system has changed.

　3. Modifying the processes and sessions values must restart the Oracle server to take effect

　 The number of connections to Oracle (sessions) is related to the number of processes in its parameter file (process), and their relationships are as follows:
Sessions= (1.1*process+5)

Pick (ii)

　 Query the number of connections to the current process of the database:
Select COUNT (*) from v$process;

　　 to view the number of connections for the current session of the database:
Elect Count (*) from v$session;

　　 to view the number of concurrent connections for a database:
Select COUNT (*) from v$session where status= ' ACTIVE ';

　　 to view the session established by the current database:
Select Sid,serial#,username,program,machine,status from V$session;

　 Maximum number of connections allowed for query database:
Select value from v$parameter where name = ' processes ';

Or: Show parameter processes;

　　 to modify the maximum number of connections allowed for a database:
alter system SET processes = + scope = SPFile;

(You need to restart the database to make changes to the number of connections)


　 To Restart the database:

Shutdown immediate;

Startup


　　 See which users are currently working with the data:


Select Osuser,a.username,cpu_time/executions/1000000| | ' S ', Sql_fulltext,machine


From V$session A,v$sqlarea b


where a.sql_address = b.address


ORDER BY cpu_time/executions Desc;


Note: UNIX 1 users session corresponds to an operating system process, while Windows embodies the thread.


Start Oracle


Su-oracle


Sqlplus system/pwd as SYSDBA//Enter SQL


Startup//Start database


Lsnrctl start//boot monitoring


Sqlplus "/as sysdba"


Shutdown immediate;


startup Mount;

ALTER DATABASE open;

However: I changed the maximum to 1200,java 356 and then the error

Oracle View and modify the maximum number of connections