OracleÊý¾Ý¿âÃÜÂëÎļþµÄά»¤£º
1. ²é¿´ÃÜÂëÎļþÖеijÉÔ±£º
¿ÉÒÔͨ¹ý²éѯÊÓͼV$PWFILE_USERSÀ´»ñȡӵÓÐSYSOPER/SYSDBAϵͳȨÏÞµÄÓû§µÄÐÅÏ¢£¬±íÖÐSYSOPER/SYSDBAÁеÄȡֵTRUE/FALSE±íʾ´ËÓû§ÊÇ·ñÓµÓÐÏàÓ¦µÄȨÏÞ¡£ÕâЩÓû§Ò²¾ÍÊÇÏàÓ¦µØ´æÔÚÓÚÃÜÂëÎļþÖеijÉÔ±¡£
2. À©Õ¹ÃÜÂëÎļþµÄÓû§ÊýÁ¿£º
µ±ÏòOracleÊý¾Ý¿âÃÜÂëÎļþÌí¼ÓµÄÕʺÅÊýÄ¿³¬¹ý´´½¨ÃÜÂëÎļþʱËù¶¨µÄÏÞÖÆ(¼´ORAPWD.EXE¹¤¾ßµÄMAX_USERS²ÎÊý)ʱ£¬ÎªÀ©Õ¹ÃÜÂëÎļþµÄÓû§ÊýÏÞÖÆ£¬ÐèÖØ½¨ÃÜÂëÎļþ£¬¾ßÌå²½ÖèÈçÏ£º
(a)²éѯÊÓͼV$PWFILE_USERS£¬¼Ç¼ÏÂÓµÓÐSYSOPER/SYSDBAϵͳȨÏÞµÄÓû§ÐÅÏ¢;
(b)¹Ø±ÕÊý¾Ý¿â;
(c) ɾ³ýÃÜÂëÎļþ;
(d) ÓÃORAPWD.EXEн¨Ò»ÃÜÂëÎļþ;
(e) ½«²½ÖèaÖлñÈ¡µÄÓû§Ìí¼Óµ½ÃÜÂëÎļþÖС£
3. ÐÞ¸ÄÃÜÂëÎļþµÄ״̬£º
ÃÜÂëÎļþµÄ״̬ÐÅÏ¢´æ·ÅÓÚ´ËÎļþÖУ¬µ±Ëü±»´´½¨Ê±£¬ËüµÄȱʡ״̬ΪSHARED¡£¿ÉÒÔͨ¹ý¸Ä±ä³õʼ»¯²ÎÊýREMOTE_LOGIN_PASSWORDFILEµÄÉèÖøıäÃÜÂëÎļþµÄ״̬¡£µ±Æô¶¯Êý¾Ý¿âÊÂÀýʱ£¬Oracleϵͳ´Ó³õʼ»¯²ÎÊýÎļþÖжÁÈ¡REMOTE_LOGIN_PASSWORDFILE²ÎÊýµÄÉèÖÃ;µ±¼ÓÔØÊý¾Ý¿âʱ£¬ÏµÍ³½«´Ë²ÎÊýÓë¿ÚÁîÎļþµÄ״̬½øÐбȽϣ¬Èç¹û²»Í¬£¬Ôò¸üÐÂÃÜÂëÎļþµÄ״̬¡£Èô¼Æ»®ÔÊÐí´Ó¶ą̀¿Í»§»úÉÏÆô¶¯Êý¾Ý¿âʵÀý£¬ÓÉÓÚ¸÷¿Í»§»úÉϱØÐëÓгõʼ»¯²ÎÊýÎļþ£¬ËùÒÔӦȷ±£¸÷¿Í»§»úÉϵijõʼ»¯²ÎÊýÎļþµÄÒ»ÖÂÐÔ£¬ÒÔ±ÜÃâÒâÍâµØ¸Ä±äÁËÃÜÂëÎļþµÄ״̬£¬Ôì³ÉÊý¾Ý¿âµÇ½µÄʧ°Ü¡£
4. ÐÞ¸ÄÃÜÂëÎļþµÄ´æ´¢Î»Öãº
ÃÜÂëÎļþµÄ´æ·ÅλÖÿÉÒÔ¸ù¾ÝÐèÒª½øÐÐÒÆ¶¯£¬µ«×÷´ËÐ޸ĺó£¬Ó¦ÏàÓ¦ÐÞ¸Äϵͳע²á¿âÓйØÖ¸ÏòÃÜÂëÎļþ´æ·ÅλÖõIJÎÊý»ò»·¾³±äÁ¿µÄÉèÖá£
Ï£ÍûÉÏÃæÕâЩÄÚÈÝÄܹ»°ïÖúÄã¸üºÃµÄѧϰÀí½âOracleÃÜÂë¹ÜÀíµÄ²Ù×÷¡£
¶«·½ÈðͨITÅàѵÓë·þÎñÖÐÐÄÓµÓÐÊ®ÄêITÅàѵ¾Ñ飬רעÖйú¸ß¶ËITÅàѵÊÇÖйú¸ß¶ËITÅàѵµÚÒ»Æ·ÅÆ£¬ÌṩȫÏßµÄITÅàѵ¿Î³Ì£¬¶«·½ÈðͨΪ¹ã´óѧԱÌá¹©È«Ãæ¡¢Ï¸Ö¡¢×¨ÒµµÄÏßÉÏ¡¢ÏßÏ·þÎñ£¬ÖÂÁ¦ÓÚΪ¿Í»§ÌáÉýÁ¼ºÃµÄÖ°Òµ¾ºÕùÁ¦http://www.easthome.com
Ïà¹ØÎĵµ£º
Èç¹û²éѯÕû¿âµÄ»°µÃÒÔDBAȨÏÞ²éѯÊý¾Ý×Öµädba_tab_columns
·ÇDBAÓû§Ö»Äܲ鿴×Ô¼ºÓжÁȡȨÏ޵ıí
¿ÉÒÔÕâÑùд²éѯ
select owner, table_name
from dba_tab_columns
where lower(column_name)='firstname';
²éѯ³öÄÄЩ±í°üº¬firstname×Ö¶ÎÒÔ¼°ÕâЩ±íÊôÓÚÄĸöÓû§
×¢£ºdba_tab_columnsÊÇÒ»¸öÊôÓÚSYSÓû§µÄÒ»¸öView ......
ÔÚOracle8i»òÒÔÉϰ汾ÖУ¬¿ÉÒÔ´´½¨ÒÔÏÂÁ½ÖÖÁÙʱ±í£º
1¡£»á»°ÌØÓеÄÁÙʱ±í
CREATE GLOBAL TEMPORARY <TABLE_NAME> (<column specification>)
&nbs ......
oracle cast() º¯ÊýÎÊÌâ
SQL> create table t1(a varchar(10));
Table created.
SQL> insert into t1 values ('12.3456');
1 row created.
SQL> select round(a) from t1;
ROUND(A)
----------
12
SQL> select round(a,3) from t1;
ROUND(A,3)
- ......
1. OracleÄÚ´æ½á¹¹¼ò½é
OracleÔÚÄÚ´æÖд洢ÒÔÏÂÐÅÏ¢£º
¡£³ÌÐò´úÂë
¡£ÒÔÁ¬½ÓµÄ»á»°ÐÅÏ¢£¬°üÀ¨µ±Ç°»î¶¯µÄ¼°·Ç»î¶¯µÄ»á»°
¡£³ÌÐòÖ´Ðйý³ÌÖÐËùÐèµÄÐÅÏ¢
¡£ÐèÒªÔÚOracle½ø³Ì¼ä¹²Ïí²¢½øÐÐͨÐŵĵÄÐÅÏ¢
¡£Êý¾ÝÎļþÄÚÊý¾ÝµÄ»º´æ£¨ÈçÊý¾Ý¿é¼°ÖØ×öÈÕÖ¾ÌõÄ¿£©
Oracle ÖеĻù±¾ÄÚ´æ½á¹¹°üÀ¨£º
¡£ÏµÍ³È«¾ÖÇø(SGA):´ËÇøÓòÓÉËùÓÐµÄ ......
µ±³õʼ»¯²ÎÊýREMOTE_LOGIN_PASSWORDFILEÉèÖÃΪEXCLUSIVEʱ£¬ÏµÍ³ÔÊÐí³ýINTERNAL/SYSÒÔÍâµÄÆäËûÓû§ÒÔ¹ÜÀíÔ±Éí·Ý´ÓÔ¶¶Ë»ò±¾»úµÇ¼µ½OracleÊý¾Ý¿âϵͳ£¬Ö´ÐÐÊý¾Ý¿â¹ÜÀí¹¤×÷;ÕâЩÓû§Ãû±ØÐë´æÔÚÓÚÃÜÂëÎļþÖУ¬ÏµÍ³²ÅÄÜʶ±ðËûÃÇ¡£ÓÉÓÚ²»¹ÜÊÇÔÚ´´½¨Êý¾Ý¿âʵÀýʱ×Ô¶¯´´½¨µÄÃÜÂëÎļþ£¬»¹ÊÇʹÓù¤¾ßORAPWD.EXEÊÖ¹¤´´½¨µÄÃÜÂëÎļþ£¬¶ ......