ORACLEµÄË÷ÒýºÍÔ¼ÊøÏê½â
* Èç¹ûij¸öÔ¼ÊøÖ»×÷ÓÃÓÚµ¥¶ÀµÄ×ֶΣ¬¼´¿ÉÒÔÔÚ×ֶμ¶¶¨ÒåÔ¼Êø£¬Ò²¿ÉÒÔÔÚ±í¼¶¶¨ÒåÔ¼Êø£¬µ«Èç¹ûij¸öÔ¼Êø×÷ÓÃÓÚ¶à¸ö×ֶΣ¬
±ØÐëÔÚ±í¼¶¶¨ÒåÔ¼Êø
* ÔÚ¶¨ÒåÔ¼ÊøÊ±¿ÉÒÔͨ¹ýCONSTRAINT¹Ø¼ü×ÖÎªÔ¼ÊøÃüÃû£¬Èç¹ûûÓÐÖ¸¶¨£¬ORACLE½«×Ô¶¯ÎªÔ¼Êø½¨Á¢Ä¬ÈϵÄÃû³Æ
¶¨Òåprimary keyÔ¼Êø(µ¥¸ö×ֶΣ©
create table employees (empno number(5) primary key,...)
Ö¸¶¨Ô¼ÊøÃû
create table employees (empno number(5) constraint emp_pk primary key,...)
¶¨Òåprimary keyÔ¼Êø(¶à¸ö×Ö¶Î,ÔÚ±í¼¶¶¨ÒåÔ¼Êø£©
create table employees
(empno number(5),
deptno number(3) not null,
constraint emp_pk primary key(empno,deptno)
using index tablespace indx
storage (initial 64K
next 64K
)
)
ORACLE×Ô¶¯»áΪ¾ßÓÐPRIMARY KEYÔ¼ÊøµÄ×Ö¶Î(Ö÷Âë×Ö¶Î)½¨Á¢Ò»¸öΨһË÷ÒýºÍÒ»¸öNOT NULLÔ¼Êø,¶¨ÒåPRIMARY KEYÔ¼ÊøÊ±¿ÉÒÔΪËüµÄË÷Òý
Ö¸¶¨´æ´¢Î»Öúʹ洢²ÎÊý
alter table employees add primary key (empno)
alter table employees add constraint emp_pk primary key (empno)
alter table employees add constraint emp_pk primary key (empno,deptno)
not nullÔ¼Êø(Ö»ÄÜÔÚ×ֶμ¶¶¨ÒåNOT NULLÔ¼Êø,ÔÚͬһ¸ö±íÖпÉÒÔ¶¨Òå¶à¸öNOT NULLÔ¼Êø)
alter table employees modify deptno not null/null
uniqueÔ¼Êø
create table employees
( empno number(5),
ename varchar2(15),
phone varchar2(15),
email varchar2(30) unique,
deptno number(3) not null,
constraint emp_ename_phone_uk unique (ename,phone)
)
alter table employees
add constraint emp_uk unique(ename,phone)
using index tablespace indx
¶¨ÒåÁËUNIQUEÔ¼ÊøµÄ×Ö¶ÎÖв»Äܰüº¬Öظ´Öµ£¬¿ÉÒÔΪһ¸ö»ò¶à¸ö×ֶζ¨ÒåUNIQUEÔ¼Êø,Òò´Ë£¬UNIQUE¼´¿ÉÒÔÔÚ×ֶμ¶Ò²¿ÉÒÔÔÚ±í¼¶¶¨Ò壬
ÔÚUNIQUEDÔ¼ÊøµÄ×Ö¶ÎÉÏ¿ÉÒÔ°üº¬¿ÕÖµ.
foreign keyÔ¼Êø
* ¶¨ÒåΪFOREIGN KEYÔ¼ÊøµÄ×Ö¶ÎÖÐÖ»Äܰüº¬ÏàÓ¦µÄÆäËü±íÖеÄÒýÓÃÂë×ֶεÄÖµ»òÕßNULLÖµ
* ¿ÉÒÔΪһ¸ö»òÕß¶à¸ö×ֶεÄ×éºÏ¶¨ÒåFOREIGN KEYÔ¼Êø
* ¶¨ÒåÁËFOREIGN KEYÔ¼ÊøµÄÍⲿÂë×ֶκÍÏà
Ïà¹ØÎĵµ£º
oracle±í¿Õ¼ä²Ù×÷Ïê½â
Ò»¡¢½¨Á¢±í¿Õ¼ä
CREATE TABLESPACE data01
DATAFILE '/oracle/oradata/db/DATA01.dbf' SIZE 500M
UNIFORM SIZE 128k;
¶þ¡¢½¨Á¢UNDO±í¿Õ¼ä
CREATE UNDO TABLESPACE UNDOTBS02
DATAFILE '/oracle/oradata/db/UNDOTBS02.dbf' SIZE 50M
#×¢Ò⣺ÔÚOPEN״̬ÏÂijЩʱ¿ÌÖ»ÄÜÓÃÒ»¸öUNDO±í¿Õ¼ä£¬Èç¹ûÒ ......
DB2 תOracle
ijÌìÊÇÐÇÆÚ¼¸µÄº¯Êý
DB2:
select a.yyxe,a.zblb,a.ysdm,a.daynum,b.zjxm from zy_yspb a ,zy_zjlb b where a.ysdm=b.id and a.ksdm=10000 order by abs( a.daynum -DAYOFWEEK(current date)+1) desc,a.daynum,a.zblb
sql.executeQuery:ORA-00936: ȱʧ±í´ïʽ
Oracle :
......
±í¿Õ¼ä×ÊÁϲéѯ
SELECT tablespace_name, block_size, extent_management, segment_space_management from dba_tablespaces;
ÅäºÍ
SELECT tablespace_name, initial_extent, next_extent, max_extents, pct_increase, min_extlen from dba_tablespaces;
ÅäºÏ
SEL ......
ORACLEµÄËø»úÖÆ
×òÌìÈ¥Ò»¸ö¹«Ë¾ÃæÊÔ£¬Îʵ½OracleµÄ·âËø»úÖÆ£¬ºÇºÇ£¬ÀíÂÛÉϵÄÎÊÌâºÃ¾Ã¶¼Ã»ÓÐѧϰÁË£¬Êé±¾µÄ¶«Î÷Ò²²î²»¶à¶¼»¹¸øÁË´óѧµÄÀÏʦ¡£»ØÀ´·ÁËÒ»ÏÂÊé±¾£¬ÕÒµ½Á˹ØÓÚÕⲿ·Ö֪ʶµÄ˵Ã÷£¬Ìù³öÀ´¹©´óѧ²Î¿¼¡££¨ÏÖÔڵĹ«Ë¾£¬ ......
´ó¿é£¬Óŵ㣺
1¡¢Ë³Ðò¶Á¡¢Ë÷Òý¶ÁÐÔÄܺÃ
ÒòΪ´ó¿éÈÝÄɵÄÐÐÏà¶ÔС¿éÊý¾Ý
¶à£¬ÔÚ½øÐÐÈ«±íɨÃèµÄʱºò£¬»òÕßË÷ÒýɨÃèµÄʱºò£¬ËùÐèÒªµÄÎïÀí¶Á¡¢Âß¼¶Á¶¼ÒªÉÙ¡£
ËüÒ²ÄܼõСË÷ÒýµÄÊ÷¸ß¡£¶ÔÓÚË÷Òý·ÃÎÊ
µÄÐÔÄÜÓÐËùÌá¸ß¡£
2¡¢´ó¿éÄÜÈÝÄɱȽϴóµÄÐÐ
ÈÝÄÉ´óÐиöÈËÀí½â£¬Ò»¶¨³Ì¶ÈÉÏ¿ÉÒÔ±ÜÃâÐÐÇ¨ÒÆ¡¢ÐÐÁ´½Ó¡£¼õС´óÐеĶÁÈ¡¿é ......