Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

×î½üÔÚ×öOracleÁÙʱ±í¼ÓÔØ ×ªÔØÒ»¸öÒÔ±ã²éѯ

×ªÔØ
DML statements on temporary tables do not generate redo logs for the data changes. However, undo logs for the data 
and redo logs for the undo logs are generated. Data from the temporary table is automatically 
dropped in the case of session termination, either when the user logs off or 
when the session terminates abnormally such as during a session or instance failure 
undo logs for the data and redo logs for the undo logs  Ç°Õß²»ÊÇ·ÅÔÚrollback segmentÖÐÂð?ÔõôÄÜдµ½redo logÖÐÈ¥ÄØ?
¸´£º ÁÙʱ±í´æ·ÅÔÚÄĶù£¿
ÁÙʱ±í¶Ôinsert/selectÐ͵ÄÓ¦ÓúÜÓÐÓᣠ
±ÈÈçÔÚ´¦Àíweb·­Ò³Ê±£¬¿ÉÒÔͨ¹ýÁÙʱ±íÀ´Ä£Äâcache·µ»Ø½á¹û¡£ 
ÏàÓ¦µÄ£¬ 
Èç¹ûÊÇupdate/select or delete selectÐ͵ÄÓ¦ÓÃʹÓÃÁÙʱ±íÊDz»Õ¼¶àÉÙÓÅÊÆµÄ¡£ 
ӦΪËäÈ»Æä²»Ö±½Óдredo£¬µ«»áͨ¹ýundo¼ä½Óдredo¡£ 
¶øinsertµÄundoÆäʵÊÇÓÃ¿Õ°×¿é»ØÐ´£¬¼¸ºõ²»Ð´redo¡£ 
ÏàÓ¦µÄupdate/deleteÐèÒª¶ÔÏà¹Ødb block×öcp undoµÄ²Ù×÷£¨ÌرðÊÇdelete£©£¬¶ÔÓ¦µÄredo¿ªÏúÒ²¶à¶àÁË¡£ 
»Ø¸´£º ÈçºÎÔÚÕû¸ösessionÖÐËø¶¨Ä³¸ö±í£¿-----------------------------7d335b34f403eaContent-Disposition
ÔÚOracle8i»òÒÔÉϰ汾ÖУ¬¿ÉÒÔ´´½¨ÒÔÏÂÁ½ÖÖÁÙʱ±í£º 
1¡£»á»°ÌØÓеÄÁÙʱ±í 
    CREATE GLOBAL TEMPORARY <TABLE_NAME> (<column specification>) 
    ON COMMIT PRESERVE ROWS£» 
2¡£ÊÂÎñÌØÓеÄÁÙʱ±í 
    CREATE GLOBAL TEMPORARY <TABLE_NAME> (<column specification>) 
    ON COMMIT DELETE ROWS£» 
   CREATE GLOBAL TEMPORARY TABLE MyTempTable 
Ëù½¨µÄÁÙʱ±íËäÈ»ÊÇ´æÔڵ쬵«ÊÇÄãÊÔÒ»ÏÂinsert Ò»Ìõ¼Ç¼ȻºóÓñðµÄÁ¬½ÓµÇÉÏÈ¥select£¬¼Ç¼Êǿյģ¬Ã÷°×Á˰ɣ¬ÎÒ°ÑÏÂÃæÁ½¾ä»°ÔÙÌùһϣº 
--ON COMMIT DELETE ROWS ˵Ã÷ÁÙʱ±íÊÇÊÂÎñÖ¸¶¨£¬Ã¿´ÎÌá½»ºóORACLE½«½Ø¶Ï±í£¨É¾³ýÈ«²¿ÐУ© 
--ON COMMIT PRESERVE ROWS ˵Ã÷ÁÙʱ±íÊǻỰָ¶¨£¬µ±ÖжϻỰʱORACLE½«½Ø¶Ï±í¡£ 
³åÍ»µÄÎÊÌâ¸ü±¾²»Óÿ¼ÂÇ. 
ÁÙʱ±íÖ»ÊDZ£´æµ±Ç°»á»°(session)Óõ½µÄÊý¾Ý£¬Êý¾ÝÖ»ÔÚÊÂÎñ»ò»á»°ÆÚ¼ä´æÔÚ¡£ 
ͨ¹ýCREATE GLOBAL TEMPORARY TABLEÃ


Ïà¹ØÎĵµ£º

OracleÖÐÓÃRowid²éÕÒºÍɾ³ýÖØ¸´¼Ç¼

OracleÖÐÓÃRowid²éÕÒºÍɾ³ýÖØ¸´¼Ç¼
¡¡¡¡Æ½Ê±¹¤×÷ÖпÉÄÜ»áÅöµ½µ±ÊÔͼ¶Ô¿â±íÖеÄijһÁлò¼¸Áд´½¨Î¨Ò»Ë÷Òýʱ£¬ÏµÍ³Ìáʾ ORA-01452 £º²»ÄÜ´´½¨Î¨Ò»Ë÷Òý£¬·¢ÏÖÖØ¸´¼Ç¼¡£
¡¡¡¡ÏÂÃæ×ܽáһϼ¸ÖÖ²éÕÒºÍɾ³ýÖØ¸´¼Ç¼µÄ·½·¨£¨ÒÔ±íCZΪÀý£©£º
¡¡¡¡±íCZµÄ½á¹¹ÈçÏ£º
¡¡¡¡SQL> desc cz
¡¡¡¡Name Null? Type
¡¡¡¡---------- ......

OracleµÄÓÅ»¯Æ÷ÓÐÁ½ÖÖÓÅ»¯·½Ê½(Ò»)

OracleµÄÓÅ»¯Æ÷ÓÐÁ½ÖÖÓÅ»¯·½Ê½(ÕûÀí), 2010-04-13
RBO·½Ê½£º»ùÓÚ¹æÔòµÄÓÅ»¯·½Ê½(Rule-Based Optimization£¬¼ò³ÆÎªRBO)
  ÓÅ»¯Æ÷ÔÚ·ÖÎöSQLÓï¾äʱ,Ëù×ñÑ­µÄÊÇOracleÄÚ²¿Ô¤¶¨µÄһЩ¹æÔò¡£±ÈÈçÎÒÃdz£¼ûµÄ£¬µ±Ò»¸öwhere×Ó¾äÖеÄÒ»ÁÐÓÐË÷Òýʱȥ×ßË÷Òý¡£
CBO·½Ê½£º»ùÓÚ´ú¼ÛµÄÓÅ»¯·½Ê½(Cost-Based Optimization£¬¼ò³ÆÎªCBO ......

OracleË÷Òý¼¼ÊõµÄÓ¦ÓÃÓëÆÊÎö


Oracle
Ë÷Òý¼¼ÊõµÄÓ¦ÓÃÓëÆÊÎö
×î
½üÕâ¶Îʱ¼ä£¬×ÜÊÇÏëдһЩÓйØÐÔÄܵ÷ÓŵÄÎÄÕ¡£µ«ÊÇ¿àÓÚûÓÐÒ»¸öʵ¼ÊµÄ°¸Àý£¬±¾ÈËÓÖ²»Ô¸¿Õ̸ÀíÂÛ£¬ÒòΪÕâЩÀíÂÛËæ±ãÔÚÍøÉϾÍÄÜÕÒµ½£¬¶øÇÒ»ù±¾ÉÏǧƪһÂÉ£¬
ÒòΪÀíÂÛÉϵÄÄÇЩ¶«Î÷¾ÍÄÇô¶à£¬ÔÙÔõô½²Ò²²»ÈçÒ»¸öʵ¼Ê°¸ÀýÉú¶¯¡£»¹ºÃÉÏÌì²»¸ºÓÐÐÄÈË£¬Ç°Ð©ÌìÈÃÎÒÅöµ½ÁËÒ»¸öʵ¼ÊµÄ°¸Àý¡£Õâ¸ö ......

Oracle ±¸·Ý Óë »Ö¸´ ¸ÅÊö


ÍæOracleÒ²ÓÐ2ÄêµÄʱ¼äÁË£¬ ÁãÁãɢɢµÄÒ²ÕûÀíһЩ×ÊÁÏ¡£ ¶«Î÷Ò»¶àÁË£¬¾ÍÀí²»Çå³þ¡£ ËùÒÔ½áºÏÕÅÏþÃ÷µÄ¡¶´ó»°Oracle RAC¡·µÄһЩÄÚÈÝ£¬ºÍ×Ô¼ºÕûÀíµÄһЩ±Ê¼Ç£¬¶ÔOracle µÄ±¸·ÝºÍ»Ö¸´×öÁËÒ»¸öϵͳµÄÕûÀí¡£ Ò²ÊÇ×Ô¼º¶Ô֪ʶµÄÒ»¸ö¹®¹Ì°É¡£ 
Ò»£® ×¼±¸ÖªÊ¶
ÏÈÀ´¿´Ò»Ð©×¼±¸ÖªÊ¶£¬Á˽â ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ