Oracle中有哪些常用的SQL语句

Oracle中有哪些常用的SQL语句，很多新手对此不是很清楚，为了帮助大家解决这个难题，下面小编将为大家详细讲解，有这方面需求的人可以来学习下，希望你能有所收获。

 查找数据库中所有字段  以对应的表
select C.column_name,C.TABLE_NAME from dba_tab_columns C where owner=''

查每个科目class 分数scro前三名
select id, name, class, scro
   from (select row_number() over(partition by class order by scro desc)  cnt,
                id,
                name,
                class,
                scro
           from student) a
  where a.cnt <= 3;

查找排序后的前三行
  select *
  from (select rw.*, rownum
          from (select *
                  from student d
                 where d.class = 'b'
                 order by d.scro desc) rw
         where rw.id >= 1
         order by rw.class desc) n
where rownum <= 3

表复制
insert into table_a (id,name,age) select b.id,b.name,b.age from table_b;

--删除表数据的触发器
CREATE OR REPLACE PROCEDURE delete_data
IS
BEGIN
   delete from test ;
   COMMIT;
EXCEPTION
   WHEN NO_DATA_FOUND
   THEN
      NULL;
   WHEN OTHERS
   THEN
      RAISE;
END delete_data;

--定时删除  每隔5分钟执行一次的计划
DECLARE
  X NUMBER;
BEGIN
  SYS.DBMS_JOB.SUBMIT
  ( job       => X
   ,what      => 'delete_data;'
   ,next_date => to_date('25/08/2008 00:00:00','dd/mm/yyyy hh34:mi:ss')
   ,interval  => 'sysdate+1/24/12'
   ,no_parse  => FALSE
  );
  SYS.DBMS_OUTPUT.PUT_LINE('Job Number is: ' || to_char(x));
COMMIT;
END;

--查看当前oracle计划
select job,next_date,next_sec,failures,broken from user_jobs;

--删除一个job
begin
dbms_job.remove(46);--46为job号
end;

--给新表插入旧表对应字段的所有数据
insert into aaa(id,name) select b.id,b.name from bbb;

文章搜索：     【点击打包该文章】
【到本站论坛,与同行交流】

select * from all_users;                ##查看所有用户
select name from v$database;             ##查看当前数据库
database test;                    ##进入test数据库
select * from v$instance;                ##查看所有的数据库实例
shutdown immediate                ##关闭数据库
alter user sys identified by new_password;        ##更改用户密码
select username,password from dba_users; ##查看当实例中的用户和密码
show parameter control_files;           ## 查看控制文件;
select member from v$logfile;        ##查看日志文件
show parameter ;                 ## 查看数据库参数
select * from user_role_privs;        ##查看当前用户的角色
select username,default_tablespace from user_users; ##查看当前用户的缺省表空间
alter user system identified by [password]        ##修改用户的密码
ALTER USER "SCOTT" ACCOUNT UNLOCK                 ##解锁SCOTT用户
show parameter processes;                    ##查看最大会话数

查看当前库的所有数据表：
SQL> select TABLE_NAME from all_tables;
select * from all_tables;
SQL> select table_name from all_tables where table_name like ‘u’;
TABLE_NAME———————————————default_auditing_options

查看表结构：desc all_tables;

创建用户并赋予权限
###----------------------------创建用户并赋予权限------------------------------------####-

create user mpss
  identified by "mpss12"
  default tablespace TS_MPSS_DATA
  temporary tablespace TEMP;
 
  给用户赋予权限
grant connect to mpss;
grant resource,create session to mpss;  开发角色
grant create procedure to dbuser； ＃这些权限足够用于开发及生产环境

给用户授权
grant dba to spms;--授予DBA权限
grant unlimited tablespace to lxg;--授予不限制的表空间
grant select any table to lxg;--授予查询任何表
grant select any dictionary to lxg;--授予 查询 任何字典

删除用户
drop user mpss cascade;

建表空间
###---------------------------------建表空间------------------------------------####-

================建立表空间============================

CREATE TABLESPACE "TS_MPSS_DATA"
    LOGGING
    DATAFILE '/mpss/data/ts_mpss_data.dbf' SIZE 1024M
    EXTENT MANAGEMENT LOCAL SEGMENT SPACE MANAGEMENT  AUTO
=====================================================
=================建立临时表空间============================

CREATE
    TEMPORARY TABLESPACE "SWVIP" TEMPFILE '/app/oracle/oradata/
    sworacle/SWVIP.dbf' SIZE 5M EXTENT MANAGEMENT LOCAL UNIFORM
    SIZE 1M
=====================================================

create tablespace TS_MPSS_DATA datafile '/mpss/data/ts_mpss_data.bdf ' size 1024m autoextend on ;      ###autoextend on 自动扩展

###------------------------------------------------------------------------------------####-

查看表空间
###----------------------------查看表空间大小------------------------------------####-
SELECT D.TABLESPACE_NAME "Name",
TO_CHAR(((((A.BYTES - DECODE(F.BYTES, NULL, 0, F.BYTES)) / 1024 / 1024)) /(A.BYTES / 1024 / 1024))*100,'99,990.9')  "used(%)",

TO_CHAR((DECODE(F.BYTES, NULL, 0, F.BYTES) / 1024 / 1024),'999,990.9') "Free (M)"

FROM SYS.DBA_TABLESPACES D, SYS.SM$TS_AVAIL A, SYS.SM$TS_FREE F
WHERE D.TABLESPACE_NAME = A.TABLESPACE_NAME
AND F.TABLESPACE_NAME (+) = D.TABLESPACE_NAME;
###--------------------------------------------------------------------------------------####-

SELECT D.TABLESPACE_NAME,SPACE "SUM_SPACE(M)",BLOCKS SUM_BLOCKS,SPACE-NVL(FREE_SPACE,0) "USED_SPACE(M)",

ROUND((1-NVL(FREE_SPACE,0)/SPACE)*100,2) "USED_RATE(%)",FREE_SPACE "FREE_SPACE(M)"

FROM
(SELECT TABLESPACE_NAME,ROUND(SUM(BYTES)/(1024*1024),2) SPACE,SUM(BLOCKS) BLOCKS
FROM DBA_DATA_FILES
GROUP BY TABLESPACE_NAME) D,
(SELECT TABLESPACE_NAME,ROUND(SUM(BYTES)/(1024*1024),2) FREE_SPACE
FROM DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME) F
WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME(+)
UNION ALL --if have tempfile
SELECT D.TABLESPACE_NAME,SPACE "SUM_SPACE(M)",BLOCKS SUM_BLOCKS,
USED_SPACE "USED_SPACE(M)",ROUND(NVL(USED_SPACE,0)/SPACE*100,2) "USED_RATE(%)",
NVL(FREE_SPACE,0) "FREE_SPACE(M)"
FROM
(SELECT TABLESPACE_NAME,ROUND(SUM(BYTES)/(1024*1024),2) SPACE,SUM(BLOCKS) BLOCKS
FROM DBA_TEMP_FILES
GROUP BY TABLESPACE_NAME) D,
(SELECT TABLESPACE_NAME,ROUND(SUM(BYTES_USED)/(1024*1024),2) USED_SPACE,
ROUND(SUM(BYTES_FREE)/(1024*1024),2) FREE_SPACE
FROM V$TEMP_SPACE_HEADER
GROUP BY TABLESPACE_NAME) F
WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME(+) ;

  查看表空间物理文件的名称及大小;
 
###--------------------表空间物理文件的名称及大小------------------------####-
  select tablespace_name, file_id, file_name,
    round(bytes/(1024*1024),0) total_space
    from dba_data_files
    order by tablespace_name;
###------------------------------------------------------------------------------------####-  

   

查看数据文件放置的路径
###------------------------------------------------------------------------------------####-  

SQL> col file_name format a50
SQL> select tablespace_name,file_id,bytes/1024/1024,file_name from dba_data_files order by file_id;

###------------------------------------------------------------------------------------####-  

    查看数据库库对象

    select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;

用系统管理员，查看当前数据库有几个用户连接：

SQL> select username,sid,serial# from v$session;

扩表空间
###------------------------------------------------------------------------------------####-

alter tablespace G000 add datafile '/dev/vgbilling/rg000_lv03' SIZE 7500m;
给表G000增加一个7500m的逻辑卷'/dev/vgbilling/rg000_lv03'
###------------------------------------------------------------------------------------####-

检查被长时间锁的对象
###------------------------------------------------------------------------------------####-

SQL>select a.session_id,a.process,a.locked_mode,b.object_name,b.object_type,b.status from v$locked_object a,dba_objects b where a.object_id=b.object_id;

###------------------------------------------------------------------------------------####-

文章出处：http://www.diybl.com/course/7_databases/oracle/Oracleshl/200899/141376.html

sys用户登陆
创建表空间：
SQL> create tablespace lmsstemp datafile 'F:\ORADATA\LMSS\LMSSTEMP01.DBF' SIZE 1
024M extent management local;

给表空间增加数据文件
alter tablespace lmsstemp add datafile 'F:\ORADATA\LMSS\LMSSTEMP02.DBF' SIZE 1
024M;

更改表空间为自动扩展
SQL> alter database datafile 'F:\ORADATA\LMSS\LMSSTEMP01.DBF' autoextend on;

查看表空间信息
SQL> select file_name,tablespace_name,autoextensible from dba_data_files;

授权：
    create any table to leon

-- Create the user （用sys执行）
create user xx  identified by xx123 default tablespace lmss temporary tablespace TEMP profile DEFAULT;

-- Grant/Revoke role privileges （用sys执行）
grant connect to xx;

--创建视图给hy用户（用leon用户）

create or replace view view_tableName as
select column。。。 from table;

-- Grant/Revoke object privileges
grant select, update on RES_XIM_CARD to hy;

--创建同义词
create synonym RES_XIM_CARD for YY.RES_XIM_CARD ;

看完上述内容是否对您有帮助呢？如果还想对相关知识有进一步的了解或阅读更多相关文章，请关注亿速云行业资讯频道，感谢您对亿速云的支持。