有时候连得上数据库,有时候又连不上.
可能是数据库上当前的连接数目已经超过了它能够处理的最大值.
SQL> selectcount(*) from v$process;--当前连接数
COUNT(*)
63
SQL> select value from v$parameter where name ='processes'--数据库允许的最大连接数
VALUE
500
修改最大连接数:
SQL> alter system set processes =2000 scope = spfile;
重启数据库:
SQL> shutdown immediate;
SQL> startup;
--查看当前有哪些用户正在使用数据
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 orderby cpu_time/executions desc;
--快速删除不活动进程
set heading off
spool on
select p.SPID from v$session s,v$process p where s.paddr= p.addr and s.machine='woogle';
spool off
set serveroutput on ;
declare
v_sid number;
v_serial number;
v_sql varchar2(200) ;
CURSOR cur_session is
select sid, serial# from v$session where machine='woogle';
begin
open cur_session ;
fetch cur_session into v_sid , v_serial ;
while cur_session%found
loop
dbms_output.put_line(v_sid ' killed!') ;
v_sql:= 'alter system kill session ' '''' v_sid ',' v_serial '''';
execute immediate v_sql ;
fetch cur_session into v_sid , v_serial ;
end loop ;
close cur_session ;
end ;
/
Linux 下快速删除不活动进程
#!/bin/bash
tmpfile=/tmp/tmp.$$
sqlplus ' / as sysdba' << EOF
set heading off
spool on
spool $tmpfile
select p.SPID from v$session s,v$process p where s.paddr= p.addr and s.STATUS='SNIPED';
spool off
set serveroutput on ;
declare
v_sid number;
v_serial number;
v_sql varchar2(200) ;
CURSOR cur_session is
select sid, serial# from v$session where STATUS='SNIPED';
begin
open cur_session ;
fetch cur_session into v_sid , v_serial ;
while cur_session%found
loop
dbms_output.put_line(v_sid ' killed!') ;
v_sql:= 'alter system kill session ' '''' v_sid ',' v_serial '''';
execute immediate v_sql ;
fetch cur_session into v_sid , v_serial ;
end loop ;
close cur_session ;
end ;
/
--转自