1、查询Oracle并发数、会话数: select count(*) from v$session #当前的连接数 select count(*) from v$session where status='ACTIVE' #并发连接数 select value from v$parameter where name = 'processes' --数据库允许的最大连接数 show parameter processes #最大连接 select username,count(username) from v$session where username is not null group by