select count(*) from v$process –当前连接数
select count(*) from v$process where program=‘ORACLE.EXE(SHAD)‘; –当前的数据库连接数
alter system set processes = 300 scope = spfile; –修改最大连接数:
show parameter processes –最大连接 这个是在command window 窗口执行的非sql语
select count(*) from v$session where status=‘ACTIVE‘ –并发连接数
select count(*) from v$session –当前的session连接数
select value from v$parameter where name =‘processes‘ –数据库允许的最大连接数
–查看当前有哪些用户正在使用数据
SELECT osuser, a.username,cpu_time/executions/1000000||‘s‘,b.sql_text,machine
from v$session a, v$sqlarea b
where a.sql_address =b.address order by cpu_time/executions desc;