ORACLE 常用脚本

ORACLE 常用脚本

作者：Fastpoint

1、查看表空间的名称及大小

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;

2、查看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;

3、查看回滚段名称及大小

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 ;

4、查看控制文件

select name from v$controlfile;

5、查看日志文件

select member from v$logfile;

6、查看表空间的使用情况

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;

7、查看数据库库对象

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

8、查看数据库的版本　

Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';

9、查看数据库的创建日期和归档方式

Select Created, Log_Mode, Log_Mode From V$Database;

1、查看当前所有对象

SQL> select * from tab;

2、建一个和a表结构一样的空表

SQL> create table b as select * from a where 1=2;

SQL> create table b(b1,b2,b3) as select a1,a2,a3 from a where 1=2;

3、察看数据库的大小，和空间使用情况

SQL> col tablespace format a20
SQL> select b.file_id　　文件ID,
　　b.tablespace_name　　表空间,
　　b.file_name　　　　　物理文件名,
　　b.bytes　　　　　　　总字节数,
　　(b.bytes-sum(nvl(a.bytes,0)))　　　已使用,
　　sum(nvl(a.bytes,0))　　　　　　　　剩余,
　　sum(nvl(a.bytes,0))/(b.bytes)*100　剩余百分比
　　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
　　/
　　dba_free_space --表空间剩余空间状况
　　dba_data_files --数据文件空间占用情况

4、查看现有回滚段及其状态

SQL> col segment format a30
SQL> SELECT SEGMENT_NAME,OWNER,TABLESPACE_NAME,SEGMENT_ID,FILE_ID,STATUS FROM DBA_ROLLBACK_SEGS;

5、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;

6、显示当前连接用户

SQL> show user

7、把SQL*Plus当计算器

SQL> select 100*20 from dual;

8、连接字符串

SQL> select 列1||列2 from 表1;
SQL> select concat(列1,列2) from 表1;

9、查询当前日期

SQL> select to_char(sysdate,'yyyy-mm-dd,hh24:mi:ss') from dual;

10、用户间复制数据

SQL> copy from user1 to user2 create table2 using select * from table1;

11、视图中不能使用order by，但可用group by代替来达到排序目的

SQL> create view a as select b1,b2 from b group by b1,b2;

12、通过授权的方式来创建用户

SQL> grant connect,resource to test identified by test;

SQL> conn test/test

How to find the tablespace of a table?

SELECT tablespace_name
FROM all_tables
WHERE table_name = 'YOURTABLENAME';

How to remove duplicate rows from a table

If the unique/primary keys can be identified from the table, it is easier to remove the records from the table using the following query:
DELETE FROM tablename
WHERE rowid not in (SELECT MIN(rowid)
FROM tablename
GROUP BY column1, column2, column3...);
Here column1, column2, column3 constitute the identifying key for each record.
If the keys cannot be identified for the table, you may create a temporary table using the query
CREATE TABLE temptablename
AS SELECT DISTINCT *
FROM tablename;
Then drop the original table and rename the temp table to original tablename.