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Oracle 9i ¿ªÊ¼¶àÁË 3 ¸ö¹ØÓÚʱ¼äµÄÊý¾ÝÀàÐÍ£ºTIMESTAMP [(precision)] TIMESTAMP [(precision)] WITH TIME ZONE TIMESTAMP [(precision)] WITH LOCAL TIME ZONE£¬ÆäÖÐ TIMESTAMP [(precision)] WITH TIME ZONE ±£´æÁËʱÇøÐÅÏ¢¡£
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Êý¾Ý¿âµÄʱÇøÔÚ´´½¨Êý¾Ý¿âʱ¿ÉÒÔͨ¹ýÔÚ create database Óï¾äÖмÓÉÏ SET TIME_ZONE = ' { { + | - } hh : mi | time_zone_region } ' À´Ö¸¶¨£¬Èç¹û£¬²»Ö¸¶¨£¬Ä¬ÈÏÊÇ°´ÕÕÊý¾Ý¿âËùÔڵIJÙ×÷ϵͳʱÇøÀ´É趨µÄ¡£´´½¨Ö®ºó£¬¿ÉÒÔͨ¹ý alter database À´Ð޸ġ£ÆäÖÐ time_zone_region ²ÎÊý¿ÉÒÔͨ¹ý²éѯ V$TIMEZONE_NAMES ¶¯Ì¬ÊÓͼÀ´»ñµÃËùÓÐÖ§³ÖµÄÖµ¡£ÐÞ¸ÄÖ®ºó£¬ÐèÒªÖØÆôÊý¾Ý¿â²ÅÄÜÉúЧ¡£¾³£ÓÐÈË»áÅöµ½ÎÞ·¨Ð޸ĵÄÇé¿ö£º
SQL> alter database set time_zone='+06:00';
alter database set time_zone='+06:00'
*
ERROR at line 1:
ORA-02231: missing or invalid option to ALTER DATABASE
TOM ¶Ô´ËÎÊÌâÓйý½âÊÍ£¬TIME_ZONE µÄÉ趨Ö÷ÒªÊÇΪÁË WITH LOCAL TIME ZONE£¬µ± session µÄʱÇøºÍÊý¾Ý¿âµÄʱÇø²»Í¬Ê±£¬oracle ¸ù¾ÝʱÇøµÄ²î¾àת»»µ½Êý¾Ý¿âµÄʱ¼ä£¬ÔÙ±£´æµ½Êý¾Ý¿âµÄ WITH LOCAL TIME ZONE ÀàÐÍÖУ¬ËûÊDz»±£´æʱÇøµÄ£¬ËùÒÔÐèÒª TIME_ZONE À´½øÐи÷ÖÖʱÇøÖ®¼äʱ¼äµÄת»»£¨WITH TIME ZONE ÀàÐͱ£´æÁËÔʼµÄʱÇø£¬ËùÒÔ²»ÐèÒª TIME_ZONE µÄÉèÖÃÒ²¿ÉÒÔ½øÐи÷ÖÖʱÇøÖ®¼äµÄת»»£©¡£µ«Êý¾Ý¿âÖÐÒ»µ©ÓÐÁ˸ÃÀàÐÍ£¬¾Í²»ÄÜͨ¹ý alter database ÐÞ¸ÄʱÇøÁË£¬»áµÃµ½ÉÏÃæµÄ´íÎ󣬿ÉÒÔͨ¹ýÏÂÃæµÄÓï¾ä»ñµÃËùÓаüº¬¸ÃÀàÐÍµÄ±í£¬½«ËûÃÇɾ³ýÖ®ºó£¬ÔÙÐ޸ġ£
select u.name || '.' || o.name || '.' || c.name TSLTZcolumn
from sys.obj$ o, sys.col$ c, sys.user$ u
where c.type# = 231
and o.obj# = c.obj#
and u.user# = o.owner#;
(Ò»°ã²éѯºóµÄ½á¹ûΪ£ºOE.ORDERS.ORDER_DATE£¬Ö¸µÄÊÇOEÓû§ÏµÄORDERS±íµÄORDER_DATE×Ö¶ÎʹÓÃÁËʱÇøµÄÐÅÏ¢£ºWITH LOCAL TIME ZONE£¬½«
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SELECT ROUND( number, [ decimalplaces ] ) from DUAL
參數:
±ØÌîÏnumber : Òª´¦ÀíµÄÊýÖµ(ÊýÖµ±í´ïʽ)
¿ÉÑ¡Ïdecimalplaces : ËÄÉáÎåÈëʱȡµÄСÊýµÄλÊý£¬²»ÌîÔò·µ»ØÕûÊý
Sample :
select round(123.456) from dual;& ......
left join ºÍ left outer join µÄÇø±ð
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A left join B µÄÁ¬½ÓµÄ¼Ç¼ÊýÓëA±íµÄ¼Ç¼Êýͬ
A right join B µÄÁ¬½Ó ......
OracleÖÐstart with...connect by prior×Ó¾äÓ÷¨
connect by Êǽṹ»¯²éѯÖÐÓõ½µÄ£¬Æä»ù±¾Óï·¨ÊÇ£º
select ... from tablename start with Ìõ¼þ1
connect by Ìõ¼þ2
where Ìõ¼þ3;
Àý£º
select * from table
start with org_id = 'HBHqfWGWPy'
connect by prior org_id = parent_id;
¼òµ ......
http://www.ej38.com/showinfo/Oracle-108709.html
Oracle 10g statisticÊý¾Ýͳ¼Æ,Oracle»á¸ù¾ÝÕâЩͳ¼ÆÐÅÏ¢À´¾ö¶¨ÊÇ×ßRBO(Rule-BasedOptimization)£¬»¹ÊÇ×ßCBO(Cost-BasedOptimization)£¬»áȥѡÔñÄÄÖÖÖ´Ðмƻ®¸ü»®Ëã,Ó°ÏìÊÇ·ñ×ßÏà¹ØµÄË÷ÒýµÈ.Èç¹ûÊÇCBOµÄ»°£¬ËüÒÀ¿¿×¼È·µÄ£¨»òÕß˵±È½Ï׼ȷµÄ£©Í³¼ÆÐÅÏ¢À´²úÉúÓÅ»¯µÄÖ ......
http://episode.javaeye.com/blog/183016
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OracleµÄUNDOTBS01.DBFÎļþÌ«´óµÄ½â¾ö°ì·¨
1¡¢.½ûÖ¹undo tablespace×Ô¶¯Ôö³¤
alter database datafile 'full_path\undotbs01.dbf' autoextend off;
2.-- ´´½¨Ò»¸öеÄС ......