1.  查看本用户下的各种对象的sql脚本
sql语句: 
表:
  select * from cat;
  select * from tab;
  select table_name from user_tables;
视图:
  select text from user_views where view_name=upper('&view_name');
索引:
  select index_name,table_owner,table_name,tablespace_name,status from user_indexes order by table_name; 
触发器:
  select trigger_name,trigger_type,table_owner,table_name,status from user_triggers;
快照:
  select owner,name,master,table_name,last_refresh,next from user_snapshots order by owner,next;
同义词:
  select * from syn;
序列:
  select * from seq;
数据库链路:
  select * from user_db_links;
约束限制:
  select table_name,constraint_name,search_condition,status from user_constraints;
本用户读取其他用户对象的权限:
  select * from user_tab_privs;
本用户所拥有的系统权限:
  select * from user_sys_privs;
用户:
  select * from all_users order by user_id;
表空间剩余自由空间情况:
  select tablespace_name,sum(bytes) 总字节数,max(bytes),count(*) from dba_free_space group by tablespace_name;
数据字典:
  select table_name from dict order by table_name;
锁及资源信息:
  select * from v$lock;不包括ddl锁
数据库字符集:
  select name,value$ from props$ where name='nls_characterset';
inin.ora参数:
  select name,value from v$parameter order by name;
sql共享池:
  select sql_text from v$sqlarea;
数据库:
  select * from v$database
控制文件:
  select * from v$controlfile;
重做日志文件信息:
  select * from v$logfile;
来自控制文件中的日志文件信息:
  select * from v$log;
来自控制文件中的数据文件信息:
  select * from v$datafile;
nls参数当前值:
  select * from v$nls_parameters;
oracle版本信息:
  select * from v$version;
描述后台进程:
  select * from v$bgprocess;
查看版本信息:
  select * from product_component_version;
2.  监控数据库
select '查看数据库的版本' from dual;
select version from product_component_version where substr(product,1,6)='oracle';
 
select '查看数据库库对象' from dual;
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
 
select '查看数据库的创建日期和归档方式' from dual;
select created, log_mode, log_mode from v$database;
 
select '查看控制文件' from dual;
select name from v$controlfile; 
 
select '查看表空间的名称及大小' from dual;
select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size from dba_tablespaces t, dba_data_files d where t.tablespace_name = d.tablespace_name group by t.tablespace_name; 
 
select '查看表空间物理文件的名称及大小' from dual;
select tablespace_name, file_id, file_name, round(bytes/(1024*1024),0) total_space from dba_data_files order by tablespace_name;
 
select '查看表空间的使用情况' from dual;
select sum(bytes)/(1024*1024) as free_space,tablespace_name from dba_free_space group by tablespace_name ;
select a.tablespace_name,a.bytes total,b.bytes used, c.bytes free, (b.bytes*100)/a.bytes "% used",(c.bytes*100)/a.bytes "% free" 
from sys.sm$ts_avail a,sys.sm$ts_used b,sys.sm$ts_free c 
where a.tablespace_name=b.tablespace_name and a.tablespace_name=c.tablespace_name;
 
select '查看日志文件' from dual;
select member from v$logfile;
 
select '查看回滚段名称及大小' from dual;
select segment_name, tablespace_name, r.status, (initial_extent/1024) initialextent,(next_extent/1024) nextextent, max_extents, v.curext curextent from dba_rollback_segs r, v$rollstat v where r.segment_id = v.usn(+) order by segment_name;