oracle9i学习笔记

oacle9i学习笔记

######### 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 onwer='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 < any (select col2 from table_name2 where continue group by col3); select * from table_name where col1 < all (select col2 from table_name2 where continue group by col3); 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<=N; /*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<=3; ############# 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));