oracle常用SQL語句
1、連接
SQL*Plus system/manager
2、顯示當前連接用戶
SQL> show user
3、查看系統擁有哪些用戶
SQL> select * from all_users;
4、新建用戶并授權
SQL> create user a identified by a;（默認建在SYSTEM表空間下）
SQL> grant connect,resource to a;
5、連接到新用戶
SQL> conn a/a
6、查詢當前用戶下所有對象
SQL> select * from tab;
7、建立第一個表
SQL> create table a(a number);
8、查詢表結構
SQL> desc a
9、插入新記錄
SQL> insert into a values(1);
10、查詢記錄
SQL> select * from a;
11、更改記錄
SQL> update a set a=2;
12、刪除記錄
SQL> delete from a;
13、回滾
SQL> roll;
SQL> rollback;
14、提交
SQL> commit;
---------------------------------------------------------------
http://www.oradb.net/newuser/cg_sys.htm
---------------------------------------------------------------
網上資料很多：
http://www.oraclefan.net/ocp/sql/dba_monitor.txt
----------------------------------------------------------------
用戶授權:
GRANT ALTER ANY INDEX TO "user_id "
GRANT "dba " TO "user_id ";
ALTER USER "user_id " DEFAULT ROLE ALL
創建用戶:
CREATE USER "user_id " PROFILE "DEFAULT " IDENTIFIED BY " DEFAULT TABLESPACE "USERS " TEMPORARY TABLESPACE "TEMP " ACCOUNT UNLOCK;
GRANT "CONNECT " TO "user_id ";
用戶密碼設定:
ALTER USER "CMSDB " IDENTIFIED BY "pass_word "
表空間創建:
CREATE TABLESPACE "table_space " LOGGING DATAFILE 'C:\ORACLE\ORADATA\dbs\table_space.ora' SIZE 5M
------------------------------------------------------------------------
1、查看當前所有對象
SQL > select * from tab;
2、建一個和a表結構一樣的空表
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、察看數據庫的大小，和空間使用情況
SQL > col tablespace format a20
SQL > select b.file_id 文件ID,
b.tablespace_name 表空間,
b.file_name 物理文件名,
b.bytes 總字節數,
(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 --表空間剩余空間狀況
dba_data_files --數據文件空間占用情況
4、查看現有回滾段及其狀態
SQL > col segment format a30
SQL > SELECT SEGMENT_NAME,OWNER,TABLESPACE_NAME,SEGMENT_ID,FILE_ID,STATUS FROM DBA_ROLLBACK_SEGS;
5、查看數據文件放置的路徑
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、顯示當前連接用戶
SQL > show user
7、把SQL*Plus當計算器
SQL > select 100*20 from dual;
8、連接字符串
SQL > select 列1 | |列2 from 表1;
SQL > select concat(列1,列2) from 表1;
9、查詢當前日期
SQL > select to_char(sysdate,'yyyy-mm-dd,hh24:mi:ss') from dual;
10、用戶間復制數據
SQL > copy from user1 to user2 create table2 using select * from table1;
11、視圖中不能使用order by，但可用group by代替來達到排序目的
SQL > create view a as select b1,b2 from b group by b1,b2;
12、通過授權的方式來創建用戶
SQL > grant connect,resource to test identified by test;
SQL > conn test/test
13、查出當前用戶所有表名。
select unique tname from col;
-----------------------------------------------------------------------
alter table alist_table add address varchar2(100);
alter table alist_table modify address varchar2(80);
create table alist_table_copy as select ID,NAME,PHONE,EMAIL,
QQ as QQ2,
ADDRESS from alist_table;
drop table alist_table;
rename alist_table_copy to alist_table
空值處理
有時要求列值不能為空
create table dept (deptno number(2) not null, dname char(14), loc char(13));
在基表中增加一列
alter table dept
add (headcnt number(3));
修改已有列屬性
alter table dept
modify dname char(20);
注：只有當某列所有值都為空時，才能減小其列值寬度。
只有當某列所有值都為空時，才能改變其列值類型。
只有當某列所有值都為不空時，才能定義該列為not null。
例：
alter table dept modify (loc char(12));
alter table dept modify loc char(12);
alter table dept modify (dname char(13),loc char(12));
查找未斷連接
select process,osuser,username,machine,logon_time ,sql_text
from v$session a,v$sqltext b where a.sql_address=b.address;
-----------------------------------------------------------------
1.以USER_開始的數據字典視圖包含當前用戶所擁有的信息, 查詢當前用戶所擁有的表信息:
select * from user_tables;
2.以ALL_開始的數據字典視圖包含ORACLE用戶所擁有的信息,
查詢用戶擁有或有權訪問的所有表信息:
select * from all_tables;
3.以DBA_開始的視圖一般只有ORACLE數據庫管理員可以訪問:
select * from dba_tables;
4.查詢ORACLE用戶：
conn sys/change_on_install
select * from dba_users;
conn system/manager;
select * from all_users;
5.創建數據庫用戶：
CREATE USER user_name IDENTIFIED BY password;
GRANT CONNECT TO user_name;
GRANT RESOURCE TO user_name;
授權的格式: grant (權限) on tablename to username;
刪除用戶(或表):
drop user(table) username(tablename) (cascade);
6.向建好的用戶導入數據表
IMP SYSTEM/MANAGER FROMUSER = FUSER_NAME TOUSER = USER_NAME FILE = C:\EXPDAT.DMP COMMIT = Y
7.索引
create index [index_name] on [table_name]( "column_name ")
Oracle維護常用SQL語句
1、查看表空間的名稱及大小
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、查看表空間物理文件的名稱及大小
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;
3、查看回滾段名稱及大小
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$logfile;
6、查看表空間的使用情況
select sum(bytes)/(1024*1024) as free_space,tablespace_name
from dba_free_space
group by tablespace_name;
SELECT A.TABLESPACE_NAME,A.BYTES TOTAL,B.BYTES USED, C.BYTES FREE,
(B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
FROM SYS.SM$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、查看數據庫庫對象
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
8、查看數據庫的版本
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
[page]
9、查看數據庫的創建日期和歸檔方式
Select Created, Log_Mode, Log_Mode From V$Database;
10、捕捉運行很久的SQL
column username format a12
column opname format a16
column progress format a8
select username,sid,opname,
round(sofar*100 / totalwork,0) '%' as progress,
time_remaining,sql_text
from v$session_longops , v$sql
where time_remaining <> 0
and sql_address = address
and sql_hash_value = hash_value
/
11、查看數據表的參數信息
SELECT partition_name, high_value, high_value_length, tablespace_name,
pct_free, pct_used, ini_trans, max_trans, initial_extent,
next_extent, min_extent, max_extent, pct_increase, FREELISTS,
freelist_groups, LOGGING, BUFFER_POOL, num_rows, blocks,
empty_blocks, avg_space, chain_cnt, avg_row_len, sample_size,
last_analyzed
FROM dba_tab_partitions
--WHERE table_name = :tname AND table_owner = :towner
ORDER BY partition_position
12、查看還沒提交的事務
select * from v$locked_object;
select * from v$transaction;
13、查找object為哪些進程所用
select
p.spid,
s.sid,
s.serial# serial_num,
s.username user_name,
a.type object_type,
s.osuser os_user_name,
a.owner,
a.object object_name,
decode(sign(48 - command),
1,
to_char(command), 'Action Code #' to_char(command) ) action,
p.program oracle_process,
s.terminal terminal,
s.program program,
s.status session_status
from v$session s, v$access a, v$process p
where s.paddr = p.addr and
s.type = 'USER' and
a.sid = s.sid and
a.object='SUBSCRIBER_ATTR'
order by s.username, s.osuser
14、回滾段查看
select rownum, sys.dba_rollback_segs.segment_name Name, v$rollstat.extents
Extents, v$rollstat.rssize Size_in_Bytes, v$rollstat.xacts XActs,
v$rollstat.gets Gets, v$rollstat.waits Waits, v$rollstat.writes Writes,
sys.dba_rollback_segs.status status from v$rollstat, sys.dba_rollback_segs,
v$rollname where v$rollname.name(+) = sys.dba_rollback_segs.segment_name and
v$rollstat.usn (+) = v$rollname.usn order by rownum
15、耗資源的進程（top session）
select s.schemaname schema_name, decode(sign(48 - command), 1,
to_char(command), 'Action Code #' to_char(command) ) action, status
session_status, s.osuser os_user_name, s.sid, p.spid , s.serial# serial_num,
nvl(s.username, '[Oracle process]') user_name, s.terminal terminal,
s.program program, st.value criteria_value from v$sesstat st, v$session s , v$processp
where st.sid = s.sid and st.statistic# = to_number('38') and ('ALL' = 'ALL'
or s.status = 'ALL') and p.addr = s.paddr order by st.value desc, p.spid asc, s.username asc, s.osuser asc