oracle常用经典SQL查询

oracle常用经典SQL查询

常用SQL查询:

 

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;

 

10、捕捉运行很久的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。查看数据表的参数信息

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.查看还没提交的事务

select * from v$locked_object;

select * from v$transaction;

 

13。查找object为哪些进程所用

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。回滚段查看

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。耗资源的进程(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$process p  
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

 

16。查看锁(lock)情况

select /*+ RULE */ ls.osuser os_user_name,   ls.username user_name,  

decode(ls.type, 'RW', 'Row wait enqueue lock', 'TM', 'DML enqueue lock', 'TX',

'Transaction enqueue lock', 'UL', 'User supplied lock') lock_type,  

o.object_name object,   decode(ls.lmode, 1, null, 2, 'Row Share', 3,

'Row Exclusive', 4, 'Share', 5, 'Share Row Exclusive', 6, 'Exclusive', null)

lock_mode,    o.owner,   ls.sid,   ls.serial# serial_num,   ls.id1,   ls.id2   

from sys.dba_objects o, (   select s.osuser,    s.username,    l.type,    

l.lmode,    s.sid,    s.serial#,    l.id1,    l.id2   from v$session s,    

v$lock l   where s.sid = l.sid ) ls  where o.object_id = ls.id1 and    o.owner

'SYS'   order by o.owner, o.object_name

 

17。查看等待(wait)情况

SELECT v$waitstat.class, v$waitstat.count count, SUM(v$sysstat.value) sum_value

FROM v$waitstat, v$sysstat WHERE v$sysstat.name IN ('db block gets',

'consistent gets') group by v$waitstat.class, v$waitstat.count

 

18。查看sga情况

SELECT NAME, BYTES FROM SYS.V_$SGASTAT ORDER BY NAME ASC

 

19。查看catched object

SELECT owner,              name,              db_link,              namespace, 

           type,              sharable_mem,              loads,              executions,  

          locks,              pins,              kept        FROM v$db_object_cache

         

20。查看V$SQLAREA

SELECT SQL_TEXT, SHARABLE_MEM, PERSISTENT_MEM, RUNTIME_MEM, SORTS,

VERSION_COUNT, LOADED_VERSIONS, OPEN_VERSIONS, USERS_OPENING, EXECUTIONS,

USERS_EXECUTING, LOADS, FIRST_LOAD_TIME, INVALIDATIONS, PARSE_CALLS, DISK_READS,

BUFFER_GETS, ROWS_PROCESSED FROM V$SQLAREA

 

21。查看object分类数量

select decode (o.type#,1,'INDEX' , 2,'TABLE' , 3 , 'CLUSTER' , 4, 'VIEW' , 5 ,

'SYNONYM' , 6 , 'SEQUENCE' , 'OTHER' ) object_type , count(*) quantity from

sys.obj$ o where o.type# > 1 group by decode (o.type#,1,'INDEX' , 2,'TABLE' , 3

, 'CLUSTER' , 4, 'VIEW' , 5 , 'SYNONYM' , 6 , 'SEQUENCE' , 'OTHER' ) union select

'COLUMN' , count(*) from sys.col$ union select 'DB LINK' , count(*) from

 

22。按用户查看object种类

select u.name schema,   sum(decode(o.type#, 1, 1, NULL)) indexes,  

sum(decode(o.type#, 2, 1, NULL)) tables,   sum(decode(o.type#, 3, 1, NULL))

clusters,   sum(decode(o.type#, 4, 1, NULL)) views,   sum(decode(o.type#, 5, 1,

NULL)) synonyms,   sum(decode(o.type#, 6, 1, NULL)) sequences,  

sum(decode(o.type#, 1, NULL, 2, NULL, 3, NULL, 4, NULL, 5, NULL, 6, NULL, 1))

others   from sys.obj$ o, sys.user$ u   where o.type# >= 1 and    u.user# =

o.owner# and   u.name 'PUBLIC'   group by u.name    order by

sys.link$ union select 'CONSTRAINT' , count(*) from sys.con$

 

23。有关connection的相关信息

1)查看有哪些用户连接

select s.osuser os_user_name,    decode(sign(48 - command), 1, to_char(command),

'Action Code #' || to_char(command) ) action,     p.program oracle_process,    

status session_status,    s.terminal terminal,    s.program program,   

s.username user_name,    s.fixed_table_sequence activity_meter,    '' query,   

0 memory,    0 max_memory,     0 cpu_usage,    s.sid,   s.serial# serial_num   

from v$session s,    v$process p   where s.paddr=p.addr and    s.type = 'USER' 

order by s.username, s.osuser

2)根据v.sid查看对应连接的资源占用等情况

select n.name,

 v.value,

 n.class,

 n.statistic# 

from  v$statname n,

 v$sesstat v

where v.sid = 71 and

 v.statistic# = n.statistic#

order by n.class, n.statistic#

3)根据sid查看对应连接正在运行的sql

select /*+ PUSH_SUBQ */

 command_type,

 sql_text,

 sharable_mem,

 persistent_mem,

 runtime_mem,

 sorts,

 version_count,

 loaded_versions,

 open_versions,

 users_opening,

 executions,

 users_executing,

 loads,

 first_load_time,

 invalidations,

 parse_calls,

 disk_reads,

 buffer_gets,

 rows_processed,

 sysdate start_time,

 sysdate finish_time,

 '>' || address sql_address,

 'N' status

from v$sqlarea

where address = (select sql_address from v$session where sid = 71)

 

24.查询表空间使用情况

select a.tablespace_name "表空间名称",

100-round((nvl(b.bytes_free,0)/a.bytes_alloc)*100,2) "占用率(%)",

round(a.bytes_alloc/1024/1024,2) "容量(M)",

round(nvl(b.bytes_free,0)/1024/1024,2) "空闲(M)",

round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",

Largest "最大扩展段(M)",

to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') "采样时间"

from  (select f.tablespace_name,

   sum(f.bytes) bytes_alloc,

   sum(decode(f.autoextensible,'YES',f.maxbytes,'NO',f.bytes)) maxbytes

from dba_data_files f

group by tablespace_name) a,

(select  f.tablespace_name,

    sum(f.bytes) bytes_free

from dba_free_space f

group by tablespace_name) b,

(select round(max(ff.length)*16/1024,2) Largest,

   ts.name tablespace_name

from sys.fet$ ff, sys.file$ tf,sys.ts$ ts

where ts.ts#=ff.ts# and ff.file#=tf.relfile# and ts.ts#=tf.ts#

group by ts.name, tf.blocks) c

where a.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name

 

25. 查询表空间的碎片程度

 

select tablespace_name,count(tablespace_name) from dba_free_space group by tablespace_name

having count(tablespace_name)>10;

 

alter tablespace name coalesce;

alter table name deallocate unused;

 

create or replace view ts_blocks_v as

select tablespace_name,block_id,bytes,blocks,'free space' segment_name from dba_free_space

union all

select tablespace_name,block_id,bytes,blocks,segment_name from dba_extents;

 

select * from ts_blocks_v;

 

select tablespace_name,sum(bytes),max(bytes),count(block_id) from dba_free_space

group by tablespace_name;

 

26。查询有哪些数据库实例在运行

select inst_name from v$active_instances;

 

===========================================================

######### 创建数据库----look $ORACLE_HOME/rdbms/admin/buildall.sql #############

 

create database db01

maxlogfiles 10

maxdatafiles 1024

maxinstances 2

logfile

GROUP 1 ('/u01/oradata/db01/log_01_db01.rdo') SIZE 15M,

GROUP 2 ('/u01/oradata/db01/log_02_db01.rdo') SIZE 15M,

GROUP 3 ('/u01/oradata/db01/log_03_db01.rdo') SIZE 15M,

datafile 'u01/oradata/db01/system_01_db01.dbf') SIZE 100M,

undo tablespace UNDO

datafile '/u01/oradata/db01/undo_01_db01.dbf' SIZE 40M

default temporary tablespace TEMP

tempfile '/u01/oradata/db01/temp_01_db01.dbf' SIZE 20M

extent management local uniform. size 128k

character set AL32UTE8

national character set AL16UTF16

set time_zone='America/New_York';

 

############### 数据字典 ##########

 

set wrap off

 

select * from v$dba_users;

 

grant select on table_name to user/rule;

 

select * from user_tables;

 

select * from all_tables;

 

select * from dba_tables;

 

revoke dba from user_name;

 

shutdown immediate

 

startup nomount

 

select * from v$instance;

 

select * from v$sga;

 

select * from v$tablespace;

 

alter session set nls_language=american;

 

alter database mount;

 

select * from v$database;

 

alter database open;

 

desc dictionary

 

select * from dict;

 

desc v$fixed_table;

 

select * from v$fixed_table;

 

set oracle_sid=foxconn

 

select * from dba_objects;

 

set serveroutput on

 

execute dbms_output.put_line('sfasd');

 

############# 控制文件 ###########

 

select * from v$database;

 

select * from v$tablespace;

 

select * from v$logfile;

 

select * from v$log;

 

select * from v$backup;

 

/*备份用户表空间*/

alter tablespace users begin backup;

 

select * from v$archived_log;

 

select * from v$controlfile;

 

alter system set control_files='$ORACLE_HOME/oradata/u01/ctrl01.ctl',

'$ORACLE_HOME/oradata/u01/ctrl02.ctl' scope=spfile;

 

cp $ORACLE_HOME/oradata/u01/ctrl01.ctl $ORACLE_HOME/oradata/u01/ctrl02.ctl

 

startup pfile='../initSID.ora'

 

select * from v$parameter where name like 'control%' ;

 

show parameter control;

 

select * from v$controlfile_record_section;

 

select * from v$tempfile;

 

/*备份控制文件*/

alter database backup controlfile to '../filepath/control.bak';

 

/*备份控制文件,并将二进制控制文件变为了asc 的文本文件*/

alter database backup controlfile to trace;

 

############### redo log ##############

 

archive log list;

 

alter system archive log start;--启动自动存档

 

alter system switch logfile;--强行进行一次日志switch

 

alter system checkpoint;--强制进行一次checkpoint

 

alter tablspace users begin backup;

 

alter tablespace offline;

 

/*checkpoint 同步频率参数FAST_START_MTTR_TARGET,同步频率越高,系统恢复所需时间越短*/

show parameter fast;

 

show parameter log_checkpoint;

 

/*加入一个日志组*/

alter database add logfile group 3 ('/$ORACLE_HOME/oracle/ora_log_file6.rdo' size 10M);

 

/*加入日志组的一个成员*/

alter database add logfile member '/$ORACLE_HOME/oracle/ora_log_file6.rdo' to group 3;

 

/*删除日志组:当前日志组不能删;活动的日志组不能删;非归档的日志组不能删*/

alter database drop logfile group 3;

 

/*删除日志组中的某个成员,但每个组的最后一个成员不能被删除*/

alter databse drop logfile member '$ORACLE_HOME/oracle/ora_log_file6.rdo';

 

/*清除在线日志*/

alter database clear logfile '$ORACLE_HOME/oracle/ora_log_file6.rdo';

 

alter database clear logfile group 3;

 

/*清除非归档日志*/

alter database clear unarchived logfile group 3;

 

/*重命名日志文件*/

alter database rename file '$ORACLE_HOME/oracle/ora_log_file6.rdo' to '$ORACLE_HOME/oracle/ora_log_file6a.rdo';

 

show parameter db_create;

 

alter system set db_create_online_log_dest_1='path_name';

 

select * from v$log;

 

select * from v$logfile;

 

/*数据库归档模式到非归档模式的互换,要启动到mount状态下才能改变;startup mount;然后再打开数据库.*/

alter database noarchivelog/archivelog;

 

achive log start;---启动自动归档

 

alter system archive all;--手工归档所有日志文件

 

select * from v$archived_log;

 

show parameter log_archive;

 

###### 分析日志文件logmnr ##############

 

1) 在init.ora中set utl_file_dir 参数

2) 重新启动oracle

3) create 目录文件

desc dbms_logmnr_d;

dbms_logmnr_d.build;

4) 加入日志文件 add/remove log file

dhms_logmnr.add_logfile

dbms_logmnr.removefile

5) start logmnr

dbms_logmnr.start_logmnr

6) 分析出来的内容查询 v$logmnr_content --sqlredo/sqlundo

 

实践:

 

desc dbms_logmnr_d;

 

/*对数据表做一些操作,为恢复操作做准备*/

update 表 set qty=10 where stor_id=6380;

 

delete 表 where stor_id=7066;

/***********************************/

utl_file_dir的路径

execute dbms_logmnr_d.build('foxdict.ora','$ORACLE_HOME/oracle/admin/fox/cdump');

 

execute dbms_logmnr.add_logfile('$ORACLE_HOME/oracle/ora_log_file6.log',dbms_logmnr.newfile);

 

execute dbms_logmnr.start_logmnr(dictfilename=>'$ORACLE_HOME/oracle/admin/fox/cdump/foxdict.ora');

 

######### tablespace ##############

 

select * form. v$tablespace;

 

select * from v$datafile;

 

/*表空间和数据文件的对应关系*/

select t1.name,t2.name from v$tablespace t1,v$datafile t2 where t1.ts#=t2.ts#;

 

alter tablespace users add datafile 'path' size 10M;

 

select * from dba_rollback_segs;

 

/*限制用户在某表空间的使用限额*/

alter user user_name quota 10m on tablespace_name;

 

create tablespace xxx [datafile 'path_name/datafile_name'] [size xxx] [extent management local/dictionary] [default storage(xxx)];

 

exmple: create tablespace userdata datafile '$ORACLE_HOME/oradata/userdata01.dbf' size 100M AUTOEXTEND ON NEXT 5M MAXSIZE 200M;

create tablespace userdata datafile '$ORACLE_HOME/oradata/userdata01.dbf' size 100M extent management dictionary default storage(initial 100k next 100k pctincrease 10) offline;

/*9i以后,oracle建议使用local管理,而不使用dictionary管理,因为local采用bitmap管理表空间 ,不会产生系统表空间的自愿争用;*/

create tablespace userdata datafile '$ORACLE_HOME/oradata/userdata01.dbf' size 100M extent management local uniform. size 1m;

create tablespace userdata datafile '$ORACLE_HOME/oradata/userdata01.dbf' size 100M extent management local autoallocate;

/*在创建表空间时,设置表空间内的段空间管理模式,这里用的是自动管理*/

create tablespace userdata datafile '$ORACLE_HOME/oradata/userdata01.dbf' size 100M extent management local uniform. size 1m segment space management auto;

 

alter tablespace userdata mininum extent 10;

 

alter tablespace userdata default storage(initial 1m next 1m pctincrease 20);

 

/*undo tablespace(不能被用在字典管理模下) */

create undo tablespace undo1 datafile '$ORACLE_HOME/oradata/undo101.dbf' size 40M extent management local;

 

show parameter undo;

 

/*temporary tablespace*/

create temporary tablespace userdata tempfile '$ORACLE_HOME/oradata/undo101.dbf' size 10m extent management local;

 

/*设置数据库缺省的临时表空间*/

alter database default temporary tablespace tablespace_name;

 

/*系统/临时/在线的undo表空间不能被offline*/

alter tablespace tablespace_name offline/online;

 

alter tablespace tablespace_name read only;

 

/*重命名用户表空间*/

alter tablespace tablespace_name rename datafile '$ORACLE_HOME/oradata/undo101.dbf' to '$ORACLE_HOME/oradata/undo102.dbf';

 

/*重命名系统表空间 ,但在重命名前必须将数据库shutdown,并重启到mount状态*/

alter database rename file '$ORACLE_HOME/oradata/system01.dbf' to '$ORACLE_HOME/oradata/system02.dbf';

 

drop tablespace userdata including contents and datafiles;---drop tablespce

 

/*resize tablespace,autoextend datafile space*/

alter database datafile '$ORACLE_HOME/oradata/undo102.dbf' autoextend on next 10m maxsize 500M;

 

/*resize datafile*/

alter database datafile '$ORACLE_HOME/oradata/undo102.dbf' resize 50m;

 

/*给表空间扩展空间*/

alter tablespace userdata add datafile '$ORACLE_HOME/oradata/undo102.dbf' size 10m;

 

/*将表空间设置成OMF状态*/

alter system set db_create_file_dest='$ORACLE_HOME/oradata';

 

create tablespace userdata;---use OMF status to create tablespace;

 

drop tablespace userdata;---user OMF status to drop tablespace;

 

select * from dba_tablespace/v$tablespace/dba_data_files;

 

/*将表的某分区移动到另一个表空间*/

alter table table_name move partition partition_name tablespace tablespace_name;

 

###### ORACLE storage structure and relationships #########

 

/*手工分配表空间段的分区(extend)大小*/

alter table kong.test12 allocate extent(size 1m datafile '$ORACLE_HOME/oradata/undo102.dbf');

 

alter table kong.test12 deallocate unused; ---释放表中没有用到的分区

 

show parameter db;

 

alter system set db_8k_cache_size=10m; ---配置8k块的内存空间块参数

 

select * from dba_extents/dba_segments/data_tablespace;

 

select * from dba_free_space/dba_data_file/data_tablespace;

 

/*数据对象所占用的字节数*/

select sum(bytes) from dba_extents where nwer='kong' and segment_name ='table_name';

 

############ UNDO Data ################

 

show parameter undo;

 

alter tablespace users offline normal;

 

alter tablespace users offline immediate;

 

recover datafile '$ORACLE_HOME/oradata/undo102.dbf';

 

alter tablespace users online ;

 

select * from dba_rollback_segs;

 

alter system set undo_tablespace=undotbs1;

 

/*忽略回滚段的错误提示*/

alter system set undo_suppress_errors=true;

 

/*在自动管理模式下,不会真正建立rbs1;在手工管理模式则可以建立,且是私有回滚段*/

create rollback segment rbs1 tablespace undotbs;

 

desc dbms_flashback;

 

/*在提交了修改的数据后,9i提供了旧数据的回闪操作,将修改前的数据只读给用户看,但这部分数据不会又恢复在表中,而是旧数据的一个映射*/

execute dbms_flashback.enable_at_time('26-JAN-04:12:17:00 pm');

 

execute dbms_flashback.disable;

 

/*回滚段的统计信息*/

select end_time,begin_time,undoblks from v$undostat;

 

/*undo表空间的大小计算公式: UndoSpace=[UR * (UPS * DBS)] + (DBS * 24)

UR :UNDO_RETENTION 保留的时间(秒)

UPS :每秒的回滚数据块

DBS:系统EXTENT和FILE SIZE(也就是db_block_size)*/

 

select * from dba_rollback_segs/v$rollname/v$rollstat/v$undostat/v$session/v$transaction;

 

show parameter transactions;

 

show parameter rollback;

 

/*在手工管理模式下,建立公共的回滚段*/

create public rollback segment prbs1 tablespace undotbs;

 

alter rollback segment rbs1 online;----在手工管理模式

 

/*在手工管理模式中,initSID.ora中指定 undo_management=manual 、rollback_segment=('rbs1','rbs2',...)、

transactions=100 、transactions_per_rollback_segment=10

然后 shutdown immediate ,startup pfile=....\???.ora */

 

########## Managing Tables ###########

 

/*char type maxlen=2000;varchar2 type maxlen=4000 bytes

rowid 是18位的64进制字符串 (10个bytes 80 bits)

rowid组成: object#(对象号)--32bits,6位

rfile#(相对文件号)--10bits,3位

block#(块号)--22bits,6位

row#(行号)--16bits,3位

64进制: A-Z,a-z,0-9,/,+ 共64个符号

 

dbms_rowid 包中的函数可以提供对rowid的解释*/

 

select rowid,dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_row_number(rowid) from table_name;

 

create table test2

(

id int,

lname varchar2(20) not null,

fname varchar2(20) constraint ck_1 check(fname like 'k%'),

empdate date default sysdate)

) tablespace tablespace_name;

 

 

create global temporary table test2 on commit delete/preserve rows as select * from kong.authors;

 

create table user.table(...) tablespace tablespace_name storage(...) pctfree10 pctused 40;

 

alter table user.tablename pctfree 20 pctused 50 storage(...);---changing table storage

 

/*手工分配分区,分配的数据文件必须是表所在表空间内的数据文件*/

alter table user.table_name allocate extent(size 500k datafile '...');

 

/*释放表中没有用到的空间*/

alter table table_name deallocate unused;

 

alter table table_name deallocate unused keep 8k;

 

/*将非分区表的表空间搬到新的表空间,在移动表空间后,原表中的索引对象将会不可用,必须重建*/

alter table user.table_name move tablespace new_tablespace_name;

 

create index index_name on user.table_name(column_name) tablespace users;

 

alter index index_name rebuild;

 

drop table table_name [CASCADE CONSTRAINTS];

 

alter table user.table_name drop column col_name [CASCADE CONSTRAINTS CHECKPOINT 1000];---drop column

 

/*给表中不用的列做标记*/

alter table user.table_name set unused column comments CASCADE CONSTRAINTS;

 

/*drop表中不用的做了标记列*/

alter table user.table_name drop unused columns checkpoint 1000;

 

/*当在drop col是出现异常,使用CONTINUE,防止重删前面的column*/

ALTER TABLE USER.TABLE_NAME DROP COLUMNS CONTINUE CHECKPOINT 1000;

 

select * from dba_tables/dba_objects;

 

######## managing indexes ##########

 

/*create index*/

example:

/*创建一般索引*/

create index index_name on table_name(column_name) tablespace tablespace_name;

/*创建位图索引*/

create bitmap index index_name on table_name(column_name1,column_name2) tablespace tablespace_name;

/*索引中不能用pctused*/

create [bitmap] index index_name on table_name(column_name) tablespace tablespace_name pctfree 20 storage(inital 100k next 100k) ;

/*大数据量的索引最好不要做日志*/

create [bitmap] index index_name table_name(column_name1,column_name2) tablespace_name pctfree 20 storage(inital 100k next 100k) nologging;

/*创建反转索引*/

create index index_name on table_name(column_name) reverse;

/*创建函数索引*/

create index index_name on table_name(function_name(column_name)) tablespace tablespace_name;

/*建表时创建约束条件*/

create table user.table_name(column_name number(7) constraint constraint_name primary key deferrable using index storage(initial 100k next 100k) tablespace tablespace_name,column_name2 varchar2(25) constraint constraint_name not null,column_name3 number(7)) tablespace tablespace_name;

 

/*给创建bitmap index分配的内存空间参数,以加速建索引*/

show parameter create_bit;

 

/*改变索引的存储参数*/

alter index index_name pctfree 30 storage(initial 200k next 200k);

 

/*给索引手工分配一个分区*/

alter index index_name allocate extent (size 200k datafile '$ORACLE/oradata/..');

 

/*释放索引中没用的空间*/

alter index index_name deallocate unused;

 

/*索引重建*/

alter index index_name rebuild tablespace tablespace_name;

 

/*普通索引和反转索引的互换*/

alter index index_name rebuild tablespace tablespace_name reverse;

 

/*重建索引时,不锁表*/

alter index index_name rebuild online;

 

/*给索引整理碎片*/

alter index index_name COALESCE;

 

/*分析索引,事实上是更新统计的过程*/

analyze index index_name validate structure;

 

desc index_state;

 

drop index index_name;

 

alter index index_name monitoring usage;-----监视索引是否被用到

 

alter index index_name nomonitoring usage;----取消监视

 

/*有关索引信息的视图*/

select * from dba_indexes/dba_ind_columns/dbs_ind_expressions/v$object_usage;

 

########## 数据完整性的管理(Maintaining data integrity) ##########

 

alter table table_name drop constraint constraint_name;----drop 约束

 

alter table table_name add constraint constraint_name primary key(column_name1,column_name2);-----创建主键

 

alter table table_name add constraint constraint_name unique(column_name1,column_name2);---创建唯一约束

 

/*创建外键约束*/

alter table table_name add constraint constraint_name foreign key(column_name1) references table_name(column_name1);

 

/*不效验老数据,只约束新的数据[enable/disable:约束/不约束新数据;novalidate/validate:不对/对老数据进行验证]*/

alter table table_name add constraint constraint_name check(column_name like 'B%') enable/disable novalidate/validate;

 

/*修改约束条件,延时验证,commit时验证*/

alter table table_name modify constraint constraint_name initially deferred;

 

/*修改约束条件,立即验证*/

alter table table_name modify constraint constraint_name initially immediate;

 

alter session set constraints=deferred/immediate;

 

/*drop一个有外键的主键表,带cascade constraints参数级联删除*/

drop table table_name cascade constraints;

 

/*当truncate外键表时,先将外键设为无效,再truncate;*/

truncate table table_name;

 

/*设约束条件无效*/

alter table table_name disable constraint constraint_name;

 

alter table table_name enable novalidate constraint constraint_name;

 

/*将无效约束的数据行放入exception的表中,此表记录了违反数据约束的行的行号;在此之前,要先建exceptions表*/

alter table table_name add constraint constraint_name check(column_name >15) enable validate exceptions into exceptions;

 

/*运行创建exceptions表的脚本*/

start $ORACLE_HOME/rdbms/admin/utlexcpt.sql;

 

/*获取约束条件信息的表或视图*/

select * from user_constraints/dba_constraints/dba_cons_columns;

 

################## managing password security and resources ####################

 

alter user user_name account unlock/open;----锁定/打开用户;

 

alter user user_name password expire;---设定口令到期

 

/*建立口令配置文件,failed_login_attempts口令输多少次后锁,password_lock_times指多少天后口令被自动解锁*/

create profile profile_name limit failed_login_attempts 3 password_lock_times 1/1440;

/*创建口令配置文件*/

create profile profile_name limit failed_login_attempts 3 password_lock_time unlimited password_life_time 30 password_reuse_time 30 password_verify_function verify_function password_grace_time 5;

/*建立资源配置文件*/

create profile prfile_name limit session_per_user 2 cpu_per_session 10000 idle_time 60 connect_time 480;

 

alter user user_name profile profile_name;

 

/*设置口令解锁时间*/

alter profile profile_name limit password_lock_time 1/24;

 

/*password_life_time指口令文件多少时间到期,password_grace_time指在第一次成功登录后到口令到期有多少天时间可改变口令*/

alter profile profile_name limit password_lift_time 2 password_grace_time 3;

 

/*password_reuse_time指口令在多少天内可被重用,password_reuse_max口令可被重用的最大次数*/

alter profile profile_name limit password_reuse_time 10[password_reuse_max 3];

 

alter user user_name identified by input_password;-----修改用户口令

 

drop profile profile_name;

 

/*建立了profile后,且指定给某个用户,则必须用CASCADE才能删除*/

drop profile profile_name CASCADE;

 

alter system set resource_limit=true;---启用自愿限制,缺省是false

 

/*配置资源参数*/

alter profile profile_name limit cpu_per_session 10000 connect_time 60 idle_time 5;

/*资源参数(session级)

cpu_per_session 每个session占用cpu的时间 单位1/100秒

sessions_per_user 允许每个用户的并行session数

connect_time 允许连接的时间 单位分钟

idle_time 连接被空闲多少时间后,被自动断开 单位分钟

logical_reads_per_session 读块数

private_sga 用户能够在SGA中使用的私有的空间数 单位bytes

 

(call级)

cpu_per_call 每次(1/100秒)调用cpu的时间

logical_reads_per_call 每次调用能够读的块数

*/

 

alter profile profile_name limit cpu_per_call 1000 logical_reads_per_call 10;

 

desc dbms_resouce_manager;---资源管理器包

 

/*获取资源信息的表或视图*/

select * from dba_users/dba_profiles;

 

###### Managing users ############

 

show parameter os;

 

create user testuser1 identified by kxf_001;

 

grant connect,createtable to testuser1;

 

alter user testuser1 quota 10m on tablespace_name;

 

/*创建用户*/

create user user_name identified by password default tablespace tablespace_name temporary tablespace tablespace_name quota 15m on tablespace_name password expire;

 

/*数据库级设定缺省临时表空间*/

alter database default temporary tablespace tablespace_name;

 

/*制定数据库级的缺省表空间*/

alter database default tablespace tablespace_name;

 

/*创建os级审核的用户,需知道os_authent_prefix,表示oracle和os口令对应的前缀,'OPS$'为此参数的值,此值可以任意设置*/

create user user_name identified by externally default OPS$tablespace_name tablespace_name temporary tablespace tablespace_name quota 15m on tablespace_name password expire;

 

/*修改用户使用表空间的限额,回滚表空间和临时表空间不允许授予限额*/

alter user user_name quota 5m on tablespace_name;

 

/*删除用户或删除级联用户(用户对象下有对象的要用CASCADE,将其下一些对象一起删除)*/

drop user user_name [CASCADE];

 

/*每个用户在哪些表空间下有些什么限额*/

desc dba_ts_quotas;select * from dba_ts_quotas where username='...';

 

/*改变用户的缺省表空间*/

alter user user_name default tablespace tablespace_name;

 

######### Managing Privileges #############

 

grant create table,create session to user_name;

 

grant create any table to user_name; revoke create any table from user_name;

 

/*授予权限语法,public 标识所有用户,with admin option允许能将权限授予第三者的权限*/

grant system_privs,[......] to [user/role/public],[....] [with admin option];

 

select * from v$pwfile_users;

 

/*当 O7_dictionary_accessiblity参数为True时,标识select any table时,包括系统表也能select ,否则,不包含系统表;缺省为false*/

show parameter O7;

 

/*由于 O7_dictionary_accessiblity为静态参数,不能动态改变,故加scope=spfile,下次启动时才生效*/

alter system set O7_dictionary_accessiblity=true scope=spfile;

 

/*授予对象中的某些字段的权限,如select 某表中的某些字段的权限*/

grant [object_privs(column,....)],[...] on object_name to user/role/public,... with grant option;

 

/*oracle不允许授予select某列的权限,但可以授insert ,update某列的权限*/

grant insert(column_name1,column_name2,...) on table_name to user_name with grant option;

 

select * from dba_sys_privs/session_privs/dba_tab_privs/user_tab_privs/dba_col_privs/user_col_privs;

 

/*db/os/none 审计被记录在 数据库/操作系统/不审计 缺省是none*/

show parameter audit_trail;

 

/*启动对表的select动作*/

audit select on user.table_name by session;

 

/*by session在每个session中发出command只记录一次,by access则每个command都记录*/

audit [create table][select/update/insert on object by session/access][whenever successful/not successful];

 

desc dbms_fga;---进一步设计,则可使用dbms_fgs包

 

/*取消审计*/

noaudit select on user.table_name;

 

/*查被审计信息*/

select * from all_def_audit_opts/dba_stmt_audit_opts/dba_priv_audit_opts/dba_obj_audit_opts;

 

/*获取审计记录*/

select * from dba_audit_trail/dba_audit_exists/dba_audit_object/dba_audit_session/dba_audit_statement;

 

########### Managing Role #################

 

create role role_name; grant select on table_name to role_name; grant role_name to user_name; set role role_name;

 

create role role_name;

create role role_name identified by password;

create role role_name identified externally;

 

set role role_name ; ----激活role

set role role_name identified by password;

 

alter role role_name not identified;

alter role role_name identified by password;

alter role role_name identified externally;

 

grant priv_name to role_name [WITH ADMIN OPTION];

grant update(column_name1,col_name2,...) on table_name to role_name;

grant role_name1 to role_name2;

 

/*建立default role,用户登录时,缺省激活default role*/

alter user user_name default role role_name1,role_name2,...;

alter user user_name default role all;

alter user user_name default role all except role_name1,...;

alter user user_name default role none;

 

set role role1 [identified by password],role2,....;

set role all;

set role except role1,role2,...;

set role none;

 

revoke role_name from user_name;

revoke role_name from public;

 

drop role role_name;

 

select * from dba_roles/dba_role_privs/role_role_privs/dba_sys_privs/role_sys_privs/role_tab_privs/session_roles;

 

########### Basic SQL SELECT ################

 

select col_name as col_alias from table_name ;

 

select col_name from table_name where col1 like '_o%'; ----'_'匹配单个字符

 

/*使用字符函数(右边截取,字段中包含某个字符,左边填充某字符到固定位数,右边填充某字符到固定位数)*/

select substr(col1,-3,5),instr(col2,'g'),LPAD(col3,10,'$'),RPAD(col4,10,'%') from table_name;

 

/*使用数字函数(往右/左几位四舍五入,取整,取余)*/

select round(col1,-2),trunc(col2),mod(col3) from table_name ;

 

/*使用日期函数(计算两个日期间相差几个星期,两个日期间相隔几个月,在某个月份上加几个月,某个日期的下一个日期,

某日期所在月的最后的日期,对某个日期的月分四舍五入,对某个日期的月份进行取整)*/

select (sysdate-col1)/7 week,months_between(sysdate,col1),add_months(col1,2),next_day(sysdate,'FRIDAY'),last_day(sysdate),

round(sysdate,'MONTH'),trunc(sysdate,'MONTH') from table_name;

 

/*使用NULL函数(当expr1为空取expr2/当expr1为空取expr2,否则取expr3/当expr1=expr2返回空)*/

select nvl(expr1,expr2),nvl2(expr1,expr2,expr3),nullif(expr1,expr2) from table_name;

 

select column1,column2,column3, case column2 when '50' then column2*1.1

when '30' then column2*2.1

when '10' then column3/20

else column3

end as ttt

from table_name ; ------使用case函数

 

select table1.col1,table2.col2 from table1

[CROSS JOIN table2] | -----笛卡儿连接

[NATURAL JOIN table2] | -----用两个表中的同名列连接

[JOIN table2 USING (column_name)] | -----用两个表中的同名列中的某一列或几列连接

[JOIN table2

ON (table1.col1=table2.col2)] |

[LEFT|RIGHT|FULL OUTER JOIN table2 ------相当于(+)=,=(+)连接,全外连接

ON (table1.col1=table2.col2)]; ------SQL 1999中的JOIN语法;

 

example:

select col1,col2 from table1 t1

join table2 t2

on t1.col1=t2.col2 and t1.col3=t2.col1

join table3 t3

on t2.col1=t3.col3;

 

select * from table_name where col1

 

select * from table_name where col1

 

insert into (select col1,col2,col3 form. table_name where col1> 50 with check option) values (value1,value2,value3);

 

MERGE INTO table_name table1

USING table_name2 table2

ON (table1.col1=table2.col2)

WHEN MATCHED THEN

UPDATE SET

table1.col1=table2.col2,

table1.col2=table2.col3,

...

WHEN NOT MATCHED THEN

INSERT VALUES(table2.col1,table2.col2,table2.col3,...); -----合并语句

 

##################### CREATE/ALTER TABLE #######################

 

alter table table_name drop column column_name ;---drop column

 

alter table table_name set unused (col1,col2,...);----设置列无效,这个比较快。

alter table table_name drop unused columns;---删除被设为无效的列

 

rename table_name1 to table_name2; ---重命名表

 

comment on table table_name is 'comment message';----给表放入注释信息

 

create table table_name

(col1 int not null,col2 varchar2(20),col3 varchar2(20),

constraint uk_test2_1 unique(col2,col3))); -----定义表中的约束条件

 

alter table table_name add constraint pk_test2 primary key(col1,col2,...); ----创建主键

 

/*建立外键*/

create table table_name (rid int,name varchar2(20),constraint fk_test3 foreign key(rid) references other_table_name(id));

 

alter table table_name add constraint ck_test3 check(name like 'K%');

 

alter table table_name drop constraint constraint_name;

 

alter table table_name drop primary key cascade;----级联删除主键

 

alter table table_name disable/enable constraint constraint_name;----使约束暂时无效

 

/*删除列,并级联删除此列下的约束条件*/

alter table table_name drop column column_name cascade constraint;

 

select * from user_constraints/user_cons_columns;---约束条件相关视图

 

############## Create Views #####################

 

CREATE [OR REPLACE] [FORCE|NOFORCE] VIEW view_name [(alias[,alias]...)]

AS subquery

[WITH CHECK OPTION [CONSTRAINT constraint_name]]

[WITH READ ONLY [CONSTRAINT constraint_name]]; ------创建视图的语法

 

example: Create or replace view testview as select col1,col2,col3 from table_name; ------创建视图

/*使用别名*/

Create or replace view testview as select col1,sum(col2) col2_alias from table_name;

/*创建复杂视图*/

Create view view_name (alias1,alias2,alias3,alias4) as select d.col1,min(e.col1),max(e.col1),avg(e.col1) from table_name1 e,table_name2 d where e.col2=d.col2 group by d.col1;

/*当用update修改数据时,必须满足视图的col1>10的条件,不满足则不能被改变.*/

Create or replace view view_name as select * from table_name where col1>10 with check option;

 

/*改变视图的值.对于简单视图可以用update语法修改表数据,但复杂视图则不一定能改。如使用了函数,group by ,distinct等的列*/

update view_name set col1=value1;

 

/*TOP-N分析*/

select [column_list],rownum from (select [column_list] from table_name order by Top-N_column) where rownum

 

/*找出某列三条最大值的记录*/

example: select rownum as rank ,col1 ,col2 from (select col1 ,col2 from table_name order by col2 desc) where rownum

 

############# Other database Object ###############

 

CREATE SEQUENCE sequence_name [INCREMENT BY n]

[START WITH n]

[{MAXVALUE n | NOMAXVALUE}]

[{MINVALUE n | NOMINVALUE}]

[{CYCEL | NOCYCLE}]

[{CACHE n | NOCACHE}]; -----创建SEQUENCE

 

example:

CREATE SEQUENCE sequence_name INCREMENT BY 10

START WITH 120

MAXVALUE 9999

NOCACHE

NOCYCLE;

 

select * from user_sequences ;---当前用户下记录sequence的视图

 

select sequence_name.nextval,sequence_name.currval from dual;-----sequence的引用

 

alter sequence sequence_name INCREMENT BY 20

MAXVALUE 999999

NOCACHE

NOCYCLE; -----修改sequence,不能改变起始序号

 

drop sequence sequence_name; ----删除sequence

 

CREATE [PUBLIC] SYNONYM synonym_name FOR object; ------创建同义词

 

DROP [PUBLIC] SYNONYM synonym_name;----删除同义词

 

CREATE PUBLIC DATABASE LINK link_name USEING OBJECT;----创建DBLINK

 

select * from object_name@link_name; ----访问远程数据库中的对象

 

/*union 操作,它将两个集合的交集部分压缩,并对数据排序*/

select col1,col2,col3 from table1_name union select col1,col2,col3 from table2_name;

 

/*union all 操作,两个集合的交集部分不压缩,且不对数据排序*/

select col1,col2,col3 from table1_name union all select col1,col2,col3 from table2_name;

 

/*intersect 操作,求两个集合的交集,它将对重复数据进行压缩,且排序*/

select col1,col2,col3 from table1_name intersect select col1,col2,col3 from table2_name;

 

/*minus 操作,集合减,它将压缩两个集合减后的重复记录, 且对数据排序*/

select col1,col2,col3 from table1_name minus select col1,col2,col3 from table2_name;

 

/*EXTRACT 抽取时间函数. 此例是抽取当前日期中的年*/

select EXTRACT(YEAR FROM SYSDATE) from dual;

/*EXTRACT 抽取时间函数. 此例是抽取当前日期中的月*/

select EXTRACT(MONTH FROM SYSDATE) from dual;

 

########################## 增强的 group by 子句 #########################

 

select [column,] group_function(column)...

from table

[WHERE condition]

[GROUP BY [ROLLUP] group_by_expression]

[HAVING having_expression];

[ORDER BY column]; -------ROLLUP操作字,对group by子句的各字段从右到左进行再聚合

 

example:

/*其结果看起来象对col1做小计*/

select col1,col2,sum(col3) from table group by rollup(col1,col2);

/*复合rollup表达式*/

select col1,col2,sum(col3) from table group by rollup((col1,col2));

 

select [column,] group_function(column)...

from table

[WHERE condition]

[GROUP BY [CUBE] group_by_expression]

[HAVING having_expression];

[ORDER BY column]; -------CUBE操作字,除完成ROLLUP的功能外,再对ROLLUP后的结果集从右到左再聚合

 

example:

/*其结果看起来象对col1做小计后,再对col2做小计,最后算总计*/

select col1,col2,sum(col3) from table group by cube(col1,col2);

/*复合rollup表达式*/

select col1,col2,sum(col3) from table group by cube((col1,col2));

/*混合rollup,cube表达式*/

select col1,col2,col3,sum(col4) from table group by col1,rollup(col2),cube(col3);

 

/*GROUPING(expr)函数,查看select语句种以何字段聚合,其取值为0或1*/

select [column,] group_function(column)...,GROUPING(expr)

from table

[WHERE condition]

[GROUP BY [ROLLUP] group_by_expression]

[HAVING having_expression];

[ORDER BY column];

 

example:

select col1,col2,sum(col3),grouping(col1),grouping(col2) from table group by cube(col1,col2);

 

/*grouping sets操作,对group by结果集先对col1求和,再对col2求和,最后将其结果集并在一起*/

select col1,col2,sum(col3) from table group by grouping sets((col1),(col2));

时间: 2024-11-10 05:19:41

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