oracle 常用脚本

/*
//查询oracle的连接数
select count(*) from v$session;
//当前用户连接数 
select count(*) from v$session t where t.username='WIMS' ;
//数据库允许的最大连接数
select value from v$parameter where name = 'processes'
//修改最大连接数:
alter system set processes = 300 scope = spfile;  

2、查询oracle的并发连接数
select count(*) from v$session where status='ACTIVE';
3、查看不同用户的连接数
select username,count(username) from v$session where username is not null group by username;
4、查看所有用户：
select * from all_users;
5、查看用户或角色系统权限(直接赋值给用户或角色的系统权限)：
select * from dba_sys_privs;
select * from user_sys_privs;
6、查看角色(只能查看登陆用户拥有的角色)所包含的权限
select * from role_sys_privs;
7、查看用户对象权限：
select * from dba_tab_privs;
select * from all_tab_privs;
select * from user_tab_privs;
8、查看所有角色：
select * from dba_roles;
9、查看用户或角色所拥有的角色：
select * from dba_role_privs;
select * from user_role_privs;
10、查看哪些用户有sysdba或sysoper系统权限(查询时需要相应权限)
select * from V$PWFILE_USERS;
 
 


重启数据库:
shutdown immediate;
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 order by cpu_time/executions desc;
select count(*) from v$session #连接数


select count(*) from v$session where status='ACTIVE'　#并发连接数

show parameter processes #最大连接

alter system set processes = value scope = spfile;




--1、查看表在那个表空间
  select tablespace_name,table_name from user_talbes where table_name='employ';
--2、获取用户的默认表空间

  select   username,   DEFAULT_TABLESPACE     from   dba_users where username='scott';
--3、查看表空间所有的文件  

  select * from dba_data_files where tablespace_name='USERS';
--4、查看表空间使用情况：
    SELECT tbs 表空间名,                                    
    sum(totalM) 总共大小M,                                    
    sum(usedM) 已使用空间M,                                    
    sum(remainedM) 剩余空间M,                                    
    sum(usedM)/sum(totalM)*100 已使用百分比,                            
    sum(remainedM)/sum(totalM)*100 剩余百分比                            
    FROM(                                            
     SELECT b.file_id ID,                                    
     b.tablespace_name tbs,                                    
     b.file_name name,                                    
     b.bytes/1024/1024 totalM,                                    
     (b.bytes-sum(nvl(a.bytes,0)))/1024/1024 usedM,                        
     sum(nvl(a.bytes,0)/1024/1024) remainedM,                            
     sum(nvl(a.bytes,0)/(b.bytes)*100),                                
     (100 - (sum(nvl(a.bytes,0))/(b.bytes)*100))                            
     FROM dba_free_space a,dba_data_files b                            
     WHERE a.file_id = b.file_id                                
     GROUP BY b.tablespace_name,b.file_name,b.file_id,b.bytes                    
     ORDER BY b.tablespace_name                                
    )                                            
    GROUP BY tbs                                        
                                                
--5、扩展表空间 

  alter database datafile 'D:OraclePRODUCTORADATATESTUSERS01.DBF' resize 50m;
  --自动增长  

  alter database datafile 'D:oraclePRODUCTORADATATESTUSERS01.DBF' autoextend on next 50m maxsize 500m;    
  --增加数据文件

   alter tablespace yourtablespacename add datafile 'd:
ewtablespacefile.dbf' size 5m;   
   
   
   */