oracle distinctÓ÷¨
distinctÕâ¸ö¹Ø¼ü×ÖÀ´¹ýÂ˵ô¶àÓàµÄÖظ´¼Ç¼ֻ±£ÁôÒ»Ìõ£¬µ«ÍùÍùÖ»Óà ËüÀ´·µ»Ø²»Öظ´¼Ç¼µÄÌõÊý£¬¶ø²»ÊÇÓÃËüÀ´·µ»Ø²»ÖؼǼµÄËùÓÐÖµ¡£ÆäÔÒòÊÇdistinctÖ»ÓÐÓöþÖØÑ»·²éѯÀ´½â¾ö£¬¶øÕâÑù¶ÔÓÚÒ»¸öÊý¾ÝÁ¿·Ç³£´óµÄÕ¾À´Ëµ£¬ÎÞÒÉÊÇ»áÖ±½ÓÓ°Ï쵽ЧÂʵġ£
ÏÂÃæÏÈÀ´¿´¿´Àý×Ó£º
table±í
×Ö¶Î1 ×Ö¶Î2
id name
1 a
2 b
3 c
4 c
5 b
¿â½á¹¹´ó¸ÅÕâÑù£¬ÕâÖ»ÊÇÒ»¸ö¼òµ¥µÄÀý×Ó£¬Êµ¼ÊÇé¿ö»á¸´Ôӵöࡣ
±ÈÈçÎÒÏëÓÃÒ»ÌõÓï¾ä²éѯµÃµ½name²»Öظ´µÄËùÓÐÊý¾Ý£¬ÄǾͱØÐëʹÓÃdistinctÈ¥µô¶àÓàµÄÖظ´¼Ç¼¡£
select distinct name from table
µÃµ½µÄ½á¹ûÊÇ:
----------
name
a
b
c
ºÃÏñ´ïµ½Ð§¹ûÁË£¬¿ÉÊÇ£¬ÎÒÏëÒªµÃµ½µÄÊÇidÖµÄØ£¿¸ÄһϲéѯÓï¾ä°É:
select distinct name, id from table
½á¹û»áÊÇ:
----------
id name
1 a
2 b
3 c
4 c
5 b
distinctÔõôûÆð×÷Óã¿×÷ÓÃÊÇÆðÁ˵ģ¬²»¹ýËûͬʱ×÷ÓÃÁËÁ½¸ö×ֶΣ¬Ò²¾ÍÊDZØÐëµÃidÓëname¶¼ÏàͬµÄ²Å»á±»Åųý¡£¡£¡£¡£¡£¡£¡£
ÎÒÃÇÔٸĸIJéѯÓï¾ä:
select id, distinct name from table
ºÜÒź¶£¬³ýÁË´íÎóÐÅÏ¢ÄãʲôҲµÃ²»µ½£¬distinct±ØÐë·ÅÔÚ¿ªÍ·¡£Äѵ½²»ÄÜ°Ñdistinct·Åµ½whereÌõ¼þÀÄÜ£¬ÕÕÑù±¨´í¡£
------------------------------------------------------------------------------------------------------------
ÏÂÃæ·½·¨¿ÉÐÐ:
select *, count(distinct name) from table group by name
½á¹û:
id name count(distinct name)
1 a 1
2 b 1
3 c 1
×îºóÒ»ÏîÊǶàÓàµÄ£¬²»ÓùܾÍÐÐÁË£¬Ä¿µÄ´ïµ½¡£¡£¡£¡£¡£
group by ±ØÐë·ÅÔÚ order by ºÍ limit֮ǰ£¬²»È»»á±¨´í
Ïà¹ØÎĵµ£º
1.¼¤»îSQL¸ú×Ù
´Óoracle10gÒÔºóÌṩÁËеķ½·¨¼¤»îSQLµÄ¸ú×Ù£¬¼´ÊÇʹÓÃdbms_monitor°üÀ´¿ªÆô»ò¹Ø±ÕSQL¸ú×Ù¡£
֮ǰ¾É·½·¨ÊÇʹÓà alter session set events .. »òÕßʹÓÃdbms_system.set_ev·½Ê½
ʹÓÃdbms_monitor°ü¿ÉÒÔÔڻỰ£¬¿Í»§¶Ë£¬×é¼þÒÔ¼°Êý¾Ý¿âËĸö²ã¼¶¿ªÆôSQLµÄ¸ú×Ù¡ ......
EMP±íÖÐÔ±¹¤ÓëÀÏ°åµÄ¹Øϵ
ÄÚÁ¬½Ó£º
ÄÚÁ¬½ÓÒ²½Ð×ÔÈ»Á¬½Ó£¬ËüÊÇ×éºÏÁ½¸ö±íµÄ³£Ó÷½·¨¡£×ÔÈ»Á¬½Ó½«Á½¸ö±íÖеÄÁнøÐбȽϣ¬½«Á½¸ö±íÖÐÂú×ãÁ¬½ÓÌõ¼þµÄÐÐ×éºÏÆðÀ´£¬×÷Ϊ½á¹û¡£×ÔÈ»Á¬½ÓÓÐÁ½ÖÖÐÎʽµÄÓï·¨¡£
select e1.ename,e1.mgr,e2.ename aa from emp e1,emp e2 where e1. ......
GSD global services daemon (GSD)
ÓëracµÄ¹ÜÀí¹¤¾ßdbca srvctl
oem½øÐн»»¥£¬ÓÃÀ´Íê³ÉʵÀýµÄÆô¶¯¹Ø±ÕµÈ¹ÜÀíÈÎÎñ¡£
ΪÁ˱£Ö¤ÕâЩ¹ÜÀí¹¤¾ßÔËÐÐÕý³£±ØÐëÔÚËùÓеĽڵãÉÏÏÈstart
gsd,²¢ÇÒÒ»¸öGSD½ø³ÌÖ§³ÖÔÚ
Ò»¸ö½ÚµãµÄ¶à¸örac.gsd½ø³ÌλÓÚ$ORACLE_HOME/binĿ¼Ï£¬ÆälogÎļþ
Ϊ$oracle_home
/srvm/log/gsdaemon.log
À ......
Ò»
.
Óû§¹ÜÀí
1.1
½¨Á¢Óû§£¨Êý¾Ý¿âÑéÖ¤£©
CREATE
USER
DAVE
IDENTIFIED
BY
pwd
DEFAULT
TABLESPACE
users
TEMPORARY
TABLESPACE  ......