Oracle·ÖÎö±íºÍË÷Òý(analyze)
analyze table tablename compute statistics;
analyze index indexname compute statistics;
¶ÔÓÚʹÓÃCBOºÜÓкô¦£¬¿ÉÒÔʹÓøü¿É¿¿µÄtableÐÅÏ¢£¬´Ó¶øÖ´Ðмƻ®Ò²¿ÉÒÔ¸ü׼ȷһЩ£¬ÔÚ10g»á×Ô¶¯analyze£¬Ö®Ç°µÄ°æ±¾ÐèÒªÊÖ¶¯¶¨ÆÚ
Éú³Éͳ¼ÆÐÅÏ¢,,Ñ¡ÔñºÏÀíµÄÖ´Ðмƻ®..
OracleµÄonline documentÕâÑùÃèÊöanalyzeµÄ×÷Óãº
Use the ANALYZE statement to collect non-optimizer statistics, for example, to:
1¡¢Collect or delete statistics about an index or index partition, table or table partition, index-organized table, cluster, or scalar object attribute.
2¡¢Validate the structure of an index or index partition, table or table partition, index-organized table, cluster, or object reference (REF).
3¡¢Identify migrated and chained rows of a table or cluster.
¶ÔÓÚÊÕ¼¯Í³¼ÆÐÅÏ¢Õâ¿é£¬ÎÒÒ»°ãʹÓÃdbms_statsÕâ¸öpackage£¬ÊÕ¼¯Í³¼ÆÐÅÏ¢µÄ×öÓÃʹCBO·½Ê½µÄÓÅ»¯Ñ¡ÔñÖ´Ðмƻ®¸ü׼ȷ¡£
ͳ¼ÆÐÅÏ¢×îºÃ¶¨ÆÚÊÕ¼¯£¬ÒÔÒµÎñµÄ²»Í¬È·¶¨²»Í¬µÄÊÕ¼¯ÖÜÆÚ¡£
Ïà¹ØÎĵµ£º
Ó¦¸¶Ä£¿éµÄ¶àÊýÒµÎñ»ùÓڲɹººÍ¿â´æµÄ²Ù×÷£¬Òò´ËÓ¦¸¶Ä£¿éµÄÔ½áÓ¦¸ÃÔڲɹºÄ£¿éºÍ¿â´æÄ£¿éÔ½áºó²ÅÄÜ¹Ø±Õ»á¼ÆÆÚ¡£
Ô½ᲽÖè
ÔÚÿ¸ö»á¼ÆÆÚÄ©£¬Ó¦¸¶Ä£¿éµÄÔ½áÓ¦×ñÑÒÔÏÂÁ÷³Ì£º
1.¼ì²éÒµÎñÊÇ·ñÈ«²¿Â¼Èë;
2.¼ì²éÊÇ·ñÓÐδÑéÖ¤¡¢Ôݹҷ¢Æ±;
3.¸üе½ÆÚµÄÔ¶ÆÚ¸¶¿î״̬;
4.¼ì²éÓ¦¸¶ÒµÎñÊÇ·ñÉú³É·Ö¼;
5.Ó¦¸¶ÒµÎñ´«Ë͵½×ÜÕÊ;
6 ......
´¦Àí·½·¨Ò» £º
¼ì²éÄǸö±í±»Ëø
select sess.sid,sess.serial#, lo.oracle_username,lo.os_user_name,ao.object_name,lo.locked_mode
from v$locked_object lo,dba_objects ao,v$session sess
where ao.object_id = lo.object_id
and lo.session_id = sess.sid;
½âËø
alter system kill session '273,45';
´¦Àí·½·¨¶ ......
OracleÓû§½âËø
¡¡¡¡Ã¿µ±ÎÒÃÇа²×°ÁËoracleºó,µÚÒ»´ÎÔËÐж¼»á³öÏÖÒ»¸öÓû§±»ËøµÄ´íÎóÌáʾ,´ËʱÐèÒªÎÒÃÇÊÖ¶¯½øÐÐÓû§½âËø,ÏÂÃæÒÔ½âËøscottÓû§ÎªÀý: Ê×ÏÈÔÚÃüÁîÐд°¿ÚÖÐÊäÈë sqlplus sys/sys as sysdba ÕâÀïµÄsysÊÇϵͳÕ˺Å,oracle×Ô´øµÄ,ºóÃæµÄsysÊÇÃÜÂë,Õâ¸öÃÜÂëÔÚÄ㰲װʱÉèÖúõÄ. as sysdba Òâ˼¾ÍÊÇÒÔÕâ¸öÓû§×öΪÊý ......
³£ÓõÄÊý¾Ý¿â×Ö¶ÎÀàÐÍÈçÏ£º
×Ö¶ÎÀàÐÍ ÖÐÎÄ˵Ã÷ ÏÞÖÆÌõ¼þ ÆäËü˵Ã÷
CHAR ¹Ì¶¨³¤¶È×Ö·û´® ×î´ó³¤¶È2000 bytes
VARCHAR2 ¿É±ä³¤¶ÈµÄ×Ö·û´® ×î´ó³¤¶È4000 bytes ¿É×öË÷ÒýµÄ×î´ó³¤¶È749
NCHAR ¸ù¾Ý×Ö·û¼¯¶ø¶¨µÄ¹Ì¶¨³¤¶È×Ö·û´® ×î´ó³¤¶È2000 bytes
NVARCHAR2 ¸ù¾Ý×Ö·û¼¯¶ø¶¨µÄ¿É±ä³¤¶È×Ö·û´® ×î´ó³¤¶È4000 bytes
DATE È ......
¡¡¡¡
¡¡¡¡±¾Êé×÷Ϊһ±¾´´×÷Ö®³õ¾Í¶¨Î»ÓÚ¼¼ÊõÓ¦ÓõÄʵ¼ù²Î¿¼Ê飬ËäȻǰǰºóºó´®ÁªÁËOracleÊý¾Ý¿âÖÐÊ®Óà¸ö³£ÓÃÌØÐÔ»ò¹¤¾ß£¬µ«ÔÚÕ½ڵÄÉè¼ÆÉÏÍêÈ«×ñÑÕâÒ»ÀíÄî¡£ÔÚÉæ¼°ÌØÐÔ»ò¹¤¾ßÓ¦ÓõÄÿһ¸öÕ½ڣ¬¾ùÓÐÏà¹ØÊµÀýÑÝʾÈçºÎÓ¦Óã¬ËùÓÐʾÀýµÄ×îÖÕÄ¿µÄ£¬¾ÍÊÇÏ£ÍûÔĶÁ±¾ÊéµÄÅóÓÑ£¬Äܹ»½«Ë«ÊÖ½â·Å³öÀ´£¬×ÔÐÅÁé»îµØÊ¹ÓÃÊéÖнéÉܵĸ÷Ï ......