查看数据库连接数、死锁
1. 查看数据库连接数
1.1 命令查看
在命令窗口输入:
show parameter processes
show parameter session
1.2 sql查询
select count(*) from v$process;
select count(*) from v$session;
2. 死锁
2.1 检查是否存在死锁
select sess.sid,
sess.serial#,
lo.oracle_username,
lo.os_user_name,
ao.object_name,
lo.locked_mode
from v$locked_object lo, dba_objects ao, v$session sess
where ao.object_id = lo.object_id
and lo.session_id = sess.sid;
2.2 检查死锁的sql
select sql_text
from v$sql
where hash_value in
(select sql_hash_value
from v$session
where sid in (select session_id from v$locked_object));
2.3 检查死锁用户和sql
select b.username, b.serial#, d.id1, a.sql_text
from v$lock d, v$session b, v$sqltext a
where b.lockwait = d.kaddr
and a.address = b.sql_address
and a.hash_value = b.sql_hash_value;
2.4 检查死锁用户和程序
select username, lockwait, status, machine, program
from v$session
where sid in (select session_id from v$locked_object);