Oracle 常用SQL命令
1、备份单张表
    创建复制表结构
    create table  employeesbak as select * from cims.employees
    如果只复制表结构,只需要在结尾加上   where 1=0
    插入数据
    insert into employeesbak
    select * from   cims.employees
   删除一条数据
   delete  from  jjl_customersource jc  where  jc.code='C0000151721' and jc.name='唐';
select * from jjl_customersource j where j.code='C0000151721';
2、Sql代码  
 --查看所有的用户  
 select * from all_users;  
 --查看当前用户信息  
 select * from user_users;  
 --查看当前用户的角色  
 select * from user_role_privs;  
 --查看当前用户的权限  
 select * from user_sys_privs;  
 --查看当前用户的表可操作权限  
 select * from user_tab_privs; 
3、获取星期几
 select to_char(sysdate,'day') dayth from dual
 5、查看所有被锁的表
 select b.owner TABLEOWNER, b.object_name TABLENAME, c.OSUSER LOCKBY,
 c.USERNAME LOGINID, c.sid SID, c.SERIAL# SERIAL
 from v$locked_object a,dba_objects b, v$session c 
 where b.object_id = a.object_id AND a.SESSION_ID =c.sid;
6、解锁表
 alter system kill session 'SID, SERIAL';
7、查看表空间的使用情况
 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$ts_free c 
 WHERE a.tablespace_name = b.tablespace_name 
 AND a.tablespace_name = c.tablespace_name; 
8、查看表空间的路径
 select tablespace_name, file_id, file_name,
 round(bytes/(1024*1024),0) total_space
 from dba_data_files where tablespace_name='SYSAUX'
 order by file_name;
9、添加数据文件
alter tablespace SYSAUX add datafile '+DATA01/wyzx/datafile/sysaux_20210430' size 10 G;
给表空间SYSAUX添加10G的数据文件
10、删掉重复项
 找出主键为nrcelldu_uk,start_time都重复的数据,只留下一条数据
delete from pm.F_5_C_S_NRCELLDU_PRB_Q a 
 where (a.nrcelldu_uk,a.start_time) in 
 (select nrcelldu_uk,start_time from pm.F_5_C_S_NRCELLDU_PRB_Q 
 group by nrcelldu_uk,start_time having count(*) > 1) 
 and rowid not in (select max(rowid) 
 from pm.F_5_C_S_NRCELLDU_PRB_Q group by nrcelldu_uk,start_time having count(*)>1
 );
 commit;
11、查看归档日志
 SELECT A.NAME, A.TOTAL_MB / 1024, A.FREE_MB / 1024 FROM V$ASM_DISKGROUP A




















