锘??xml version="1.0" encoding="utf-8" standalone="yes"?>亚洲精品高清国产一线久久,亚洲精品尤物yw在线影院,亚洲精品自在线拍http://m.tkk7.com/1948asd/category/39007.htmlzh-cnTue, 12 May 2009 14:17:32 GMTTue, 12 May 2009 14:17:32 GMT60鏁版嵁搴撳涔?/title><link>http://m.tkk7.com/1948asd/archive/2009/05/11/270068.html</link><dc:creator>鎴戞槸鑿滈笩</dc:creator><author>鎴戞槸鑿滈笩</author><pubDate>Mon, 11 May 2009 08:37:00 GMT</pubDate><guid>http://m.tkk7.com/1948asd/archive/2009/05/11/270068.html</guid><wfw:comment>http://m.tkk7.com/1948asd/comments/270068.html</wfw:comment><comments>http://m.tkk7.com/1948asd/archive/2009/05/11/270068.html#Feedback</comments><slash:comments>1</slash:comments><wfw:commentRss>http://m.tkk7.com/1948asd/comments/commentRss/270068.html</wfw:commentRss><trackback:ping>http://m.tkk7.com/1948asd/services/trackbacks/270068.html</trackback:ping><description><![CDATA[ <br />鏁版嵁綆＄悊鎶鏈粡鍘嗕簡(jiǎn)浜哄伐綆＄悊銆佹枃浠剁郴緇熴佹暟鎹簱鍜岄珮綰ф暟鎹簱鎶鏈瓑鍥涗釜闃舵銆?br />鏁版嵁搴撶郴緇熸槸鍦ㄦ枃浠剁郴緇熺殑鍩虹涓婂彂灞曡屾垚鐨勶紝鍚屾椂鍙堝厠鏈嶄簡(jiǎn)鏂囦歡緋葷粺鐨勪笁涓己闄鳳細(xì)鏁版嵁鐨勫啑浣欍佷笉涓鑷存у拰鑱旂郴寮便?br /><br />鏁版嵁妯″瀷鏄鐜板疄涓栫晫榪涜鎶借薄鐨勫伐鍏鳳紝鐢ㄤ簬鎻忚堪鐜板疄涓栫晫鐨勬暟鎹佹暟鎹仈緋匯佹暟鎹涔夊拰鏁版嵁綰︽潫絳夋柟闈㈠唴瀹廣傛暟鎹ā鍨嬪垎鎴愭蹇墊ā鍨嬪拰緇撴瀯妯″瀷涓ゅぇ綾匯傚墠鑰呯殑浠ｈ〃鏄疄浣撹仈緋繪ā鍨嬶紝鍚庤呯殑浠ｈ〃鏄眰嬈°佺綉鐘躲佸叧緋誨拰闈㈠悜瀵硅薄妯″瀷銆傚叧緋繪ā鍨嬫槸褰撲粖鐨勪富嫻佹ā鍨嬶紝闈㈠悜瀵硅薄妯″瀷鏄粖鍚庡彂灞曠殑鏂瑰悜銆?br /><br />鏁版嵁搴撴槸瀛樺偍鍦ㄤ竴璧烽泦涓鐞嗙殑鐩稿叧鏁版嵁鐨勯泦鍚堛傛暟鎹簱鐨勪綋緋葷粨鏋勬槸瀵規(guī)暟鎹殑涓変釜鎶借薄綰у埆銆傚畠鎶婃暟鎹殑鍏蜂綋緇勭粐鐣欑粰DBMS鍘誨仛錛岀敤鎴峰彧闇鎶借薄鍦板鐞嗛昏緫鏁版嵁錛岃屼笉蹇呭叧蹇?jī)鏁版嵁鍦ㄨ绠楁溵Z腑鐨勫瓨鍌紝鍑忚交浜?jiǎn)鐢ㄦ埛鋴社敤绯痪l熺殑璐熸媴銆傜敱浜庝笁綰х粨鏋勪箣闂村線寰宸埆寰堝ぇ錛屽瓨鍦ㄧ潃涓ょ駭鏄犺薄錛屽洜姝や嬌DBS鍏鋒湁杈冮珮鐨勬暟鎹嫭绔嬫э細(xì)鐗╃悊鏁版嵁鐙珛鎬у拰閫昏緫鏁版嵁鐙珛鎬с?br /><br />鏁版嵁鐙珛鎬ф槸鎸囧湪鏌愪釜灞傛涓婁慨鏀規(guī)ā寮忚屼笉褰卞搷杈冮珮?shù)竴灞傛ā寮忕殑鑳藉姏銆?br />DBMS鏄綅浜庣敤鎴蜂笌OS涔嬮棿鐨勪竴灞傛暟鎹鐞嗚蔣浠躲傛暟鎹簱璇█鍒嗘垚DDL鍜孌ML涓ょ被銆侱BMS涓昏鐢辨煡璇㈠鐞嗗櫒鍜屽瓨鍌ㄧ鐞嗗櫒涓ゅぇ閮ㄥ垎緇勬垚銆?br />DBS鏄寘鍚獶B鍜孌BMS鐨勮綆楁満緋葷粺銆侱BS鐨勫叏灞緇撴瀯浣撶幇浜?jiǎn)DBS鐨勬ā鍧楀姛鑳界粨鏋勩?br /><br /><strong>鏁版嵁搴撲笁綰т綋緋葷粨鏋勶細(xì)<br /><img height="576" alt="fsdafsd.jpg" src="http://m.tkk7.com/images/blogjava_net/1948asd/fsdafsd.jpg" width="702" border="0" /><br /><img height="1" src="/WebResource.axd?d=pLXXeGbWF7eXU8SMs2-GFZvUWY2JNH05dFx5YzJhGUYAYJAFEaTEq36NAhTPy7_KekvzDFwt8wvQWdByvJIGWdEq6x2KpKD80&t=633043282320000000" width="1" /><br /><br /></strong><br /><strong>鏁版嵁搴撲綋緋葷粨鏋勪簲瑕佺礌:</strong><br />1銆佹蹇墊ā寮忔槸鏁版嵁搴撲腑鍏ㄩ儴鏁版嵁鐨勬暣浣撻昏緫緇撴瀯鐨勬弿榪般?br />2銆佸妯″紡鏄敤鎴峰啓鏁版嵁搴撶郴緇熺殑鎺ュ彛錛屾槸鐢ㄦ埛鐢ㄥ埌閭ｉ儴鍒嗘暟鎹殑鎻忚堪銆?br />3銆佸唴妯″紡鏄暟鎹簱鍦ㄧ墿鐞嗗瓨鍌ㄦ柟闈㈢殑鎻忚堪錛屽畾涔夊唴閮ㄨ褰曠被鍨嬨佺儲(chǔ)寮曞拰鏂囦歡鐨勭粍緇囨柟寮忥紝浠ュ強(qiáng)鏁版嵁鎺у埗鏂歸潰鐨勭粏鑺傘?br />4銆佹ā寮忥紡鍐呮ā寮忔槧璞″瓨鍦ㄤ簬姒傚康綰у拰鍐呴儴綰т箣闂達(dá)紝鐢ㄤ簬瀹氫箟姒傚康妯″紡鍜屽唴妯″紡涔嬮棿鐨勫搴旀с?br />5銆佸妯″紡錛忔ā寮忔槧璞″瓨鍦ㄤ簬澶栭儴綰у拰姒傚康綰т箣闂達(dá)紝鐢ㄤ簬瀹氫箟澶栨ā寮忓拰姒傚康妯″紡涔嬮棿鐨勫搴旀с?br /><br /><strong>聽(tīng)DBMS鐨勬ā鍧楃粍鎴愶細(xì)<br /></strong><br />鏌ヨ澶勭悊鍣ㄦ湁鍥涗釜涓昏鎴愬垎錛欴DL緙栬瘧鍣紝DML緙栬瘧鍣紝宓屽叆寮廌ML鐨勯緙栬瘧鍣ㄥ強(qiáng)鏌ヨ榪愯鏍稿績(jī)紼嬪簭銆?br />瀛樺偍綆＄悊鍣ㄦ湁鍥涗釜涓昏鎴愬垎錛氭潈闄愬拰瀹屾暣鎬х鐞嗗櫒錛屼簨鍔＄鐞嗗櫒錛屾枃浠剁鐞嗗櫒鍙?qiáng)缂撳啿鍖航帯鐞嗗櫒銆?br /><br /><strong>DBS鐨勫叏灞緇撴瀯錛?br /><br /><img height="1" src="/WebResource.axd?d=pLXXeGbWF7eXU8SMs2-GFZvUWY2JNH05dFx5YzJhGUYAYJAFEaTEq36NAhTPy7_KekvzDFwt8wvQWdByvJIGWdEq6x2KpKD80&t=633043282320000000" width="1" /><img height="593" alt="ttttt.jpg" src="http://m.tkk7.com/images/blogjava_net/1948asd/ttttt.jpg" width="510" border="0" /><br /></strong><br /><br /><strong>DBS緇撴瀯鐨勫垎綾伙細(xì)<br /></strong><br />闆嗕腑寮廌BS錛坈entralized DBS錛?br />瀹㈡埛鏈猴紡鏈嶅姟鍣ㄥ紡DBS錛坈lient/server DBS錛岃涓篊/S DBS錛?br />騫惰寮廌BS錛坧arallel DBS錛?br />鍒嗗竷寮廌BS錛坉istributed DBS錛?br /><br /><br /><strong>DBA鐨勪富瑕佽亴璐ｆ湁浠ヤ笅鍏偣錛?/strong><br />1銆佸畾涔夋ā寮忋?br />2銆佸畾涔夊唴妯″紡銆?br />3銆佷笌鐢ㄦ埛鐨勮仈緇溿傚寘鎷畾涔夊妯″紡銆佸簲鐢ㄧ▼搴忕殑璁捐銆佹彁渚涙妧鏈煿璁瓑涓撲笟鏈嶅姟銆?br />4銆佸畾涔夊畨鍏ㄦц鍒欙紝瀵圭敤鎴瘋闂暟鎹簱鐨勬巿鏉冦?br />5銆佸畾涔夊畬鏁存ц鍒欙紝鐩戠潱鏁版嵁搴撶殑榪愯銆?br />6銆佹暟鎹簱鐨勮漿鍌ㄤ笌鎭㈠宸ヤ綔銆?img src ="http://m.tkk7.com/1948asd/aggbug/270068.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://m.tkk7.com/1948asd/" target="_blank">鎴戞槸鑿滈笩</a> 2009-05-11 16:37 <a href="http://m.tkk7.com/1948asd/archive/2009/05/11/270068.html#Feedback" target="_blank" style="text-decoration:none;">鍙戣〃璇勮</a></div>]]></description></item><item><title>oracle 鏉冮檺綆＄悊http://m.tkk7.com/1948asd/archive/2009/04/13/265303.html鎴戞槸鑿滈笩鎴戞槸鑿滈笩Mon, 13 Apr 2009 07:42:00 GMThttp://m.tkk7.com/1948asd/archive/2009/04/13/265303.htmlhttp://m.tkk7.com/1948asd/comments/265303.htmlhttp://m.tkk7.com/1948asd/archive/2009/04/13/265303.html#Feedback0http://m.tkk7.com/1948asd/comments/commentRss/265303.htmlhttp://m.tkk7.com/1948asd/services/trackbacks/265303.html

緋葷粺鏉冮檺錛?br />grant create session to li;//涓虹敤鎴鋒巿浜堣闂暟鎹簱鐨勬潈闄愩?br />grant create table to li;//涓虹敤鎴鋒巿浜堝垱寤烘暟鎹簱鐨勬潈闄愩?br />grant unlimited tablespace //涓虹敤鎴鋒巿浜堟病鏈変笂闄愮殑紜壇璁塊棶琛ㄧ┖闂寸殑鏉冮檺銆?br />revoke table from li;//;//鍒犻櫎鐢ㄦ埛鎺堜簣鍒涘緩鏁版嵁搴撶殑鏉冮檺銆?br />revoke unlimited tablespace //鍒犻櫎鐢ㄦ埛鎺堜簣娌℃湁涓婇檺鐨勭‘鑹闂〃絀洪棿鐨勬潈闄愩?br />grant create session to public //鎵鏈夐兘鏈?br />鏁版嵁瀛楀吀錛?br />select * from user_sys_privs;//褰撳墠鐢ㄦ埛鎷ユ湁鏉冮檺

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瀵硅薄鏉冮檺錛氳皝鎷ユ湁璋佸氨鍙互鎺堟潈

grant select on mytab to lisi ;//璁﹍isi 鏈夎闂甽i鎷ユ湁鐨刴ytab鐨勬煡璇㈡潈闄?br />
grant insert on mytab to lisi ;//璁﹍isi 鏈夎闂甽i鎷ユ湁鐨刴ytab鐨勬彃鍏ユ潈闄?br />

grant all on mytab to lisi;//鎵鏈夋潈闄愯祴浜?lisi;

鏁版嵁瀛楀吀錛?br />select * from user_tab_privs;

grant create session to public //鎵鏈?br />
瀵硅薄鏉冮檺鎺у埗鍒板垪

grant update(name)聽(tīng) on mytab to lisi;//聽(tīng) 鎺堜簣lisi鍙兘鏇存柊name灞炴?涓哄瓧孌靛垎閰嶆潈闄愶細(xì)聽(tīng)鍙兘鏄彃鍏ュ拰鏇存柊)





]]>Oracle璋冧紭錛堣漿錛?/title><link>http://m.tkk7.com/1948asd/archive/2009/04/13/265213.html</link><dc:creator>鎴戞槸鑿滈笩</dc:creator><author>鎴戞槸鑿滈笩</author><pubDate>Mon, 13 Apr 2009 00:57:00 GMT</pubDate><guid>http://m.tkk7.com/1948asd/archive/2009/04/13/265213.html</guid><wfw:comment>http://m.tkk7.com/1948asd/comments/265213.html</wfw:comment><comments>http://m.tkk7.com/1948asd/archive/2009/04/13/265213.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://m.tkk7.com/1948asd/comments/commentRss/265213.html</wfw:commentRss><trackback:ping>http://m.tkk7.com/1948asd/services/trackbacks/265213.html</trackback:ping><description><![CDATA[ <p> <span id="lpzrpjd" class="bold"> <span id="pbjpndn" class="smalltxt"> <strong> <font face="Comic Sans MS">Oracle璋冧紭(鍏ラ棬鍙?qiáng)鎻愰珮绡?</font> </strong> </span> </span> </p> <p> <span id="rntfbjt" class="bold"> <span id="jlvzdjb" class="smalltxt"> <strong> <font face="Comic Sans MS"> <font size="1"> <br /> </font> <br /> </font> </strong> </span> </span>鍦ㄨ繃鍘葷殑鍗佸勾涓紝 Oracle 宸茬粡鎴愪負(fù)涓栫晫涓婃渶涓撲笟鐨勬暟鎹簱涔嬩竴銆傚浜?IT 涓撳鏉ヨ錛屽氨鏄紜繚鍒╃敤 Oracle 鐨勫己澶х壒鎬ф潵鎻愰珮?shù)粬浠叕鍙哥殑鐢熶骇鍔涖傛渶鏈夋晥鐨勬柟娉曚箣涓鏄氳繃 Oracle 璋冧紭銆傚畠鏈夊ぇ閲忕殑璋冩暣鍙傛暟鍜屾妧鏈潵鏀硅繘浣犵殑 Oracle 鏁版嵁搴撶殑鎬ц兘銆?<br />Oracle 璋冧紭鏄竴涓鏉傜殑涓婚銆傚叧浜庤皟浼樺彲浠ュ啓鏁存暣涓鏈功錛屼笉榪囷紝涓轟簡(jiǎn)鏀瑰杽 Oracle 鏁版嵁搴撶殑鎬ц兘錛屾湁涓浜涘熀鏈殑姒傚康鏄瘡涓?Oracle DBA 閮藉簲璇ラ伒浠庣殑銆?<br />銆銆 鍦ㄨ繖綃囩畝浠嬩腑錛屾垜浠皢綆瑕佸湴浠嬬粛浠ヤ笅鐨?Oracle 涓婚錛?<br />銆銆-- 澶栭儴璋冩暣錛氭垜浠簲璇ヨ浣?Oracle 騫朵笉鏄崟鐙繍琛岀殑銆傚洜姝ゆ垜浠皢鏌ョ湅涓涓嬮氳繃璋冩暣 Oracle 鏈嶅姟鍣ㄤ互寰楀埌楂樼殑鎬ц兘銆?<br />銆銆--Row re-sequencing 浠ュ噺灝戠鐩?I/O 錛氭垜浠簲璇ユ噦寰?Oracle 璋冧紭鏈閲嶈鐨勭洰鏍囨槸鍑忓皯 I/O 銆?<br />銆銆--Oracle SQL 璋冩暣銆?Oracle SQL 璋冩暣鏄?Oracle 璋冩暣涓渶閲嶈鐨勯鍩熶箣涓錛屽彧瑕侀氳繃涓浜涚畝鍗曠殑 SQL 璋冧紭瑙勫垯灝卞彲浠ュぇ騫呭害鍦版彁鍗?SQL 璇彞鐨勬ц兘錛岃繖鏄竴鐐歸兘涓嶅鎬殑銆?<br />銆銆-- 璋冩暣 Oracle 鎺掑簭錛氭帓搴忓浜?Oracle 鎬ц兘涔熸槸鏈夊緢澶у獎(jiǎng)鍝嶇殑銆?<br />銆銆-- 璋冩暣 Oracle 鐨勭珵浜夛細(xì)琛ㄥ拰绱㈠紩鐨勫弬鏁拌緗浜?UPDATE 鍜?INSERT 鐨勬ц兘鏈夊緢澶х殑褰卞搷銆?<br /><br />銆銆 鎴戜滑棣栧厛浠庤皟鏁?Oracle 澶栭儴鐨勭幆澧冨紑濮嬨傚鏋滃唴瀛樺拰 CPU 鐨勮祫婧愪笉瓚崇殑璇濓紝浠諱綍鐨?Oracle 璋冩暣閮芥槸娌℃湁甯姪鐨勩?<br /><br />銆銆澶栭儴鐨勬ц兘闂 <br />銆銆<br />銆銆Oracle 騫朵笉鏄崟鐙繍琛岀殑銆?Oracle 鏁版嵁搴撶殑鎬ц兘鍜屽閮ㄧ殑鐜鏈夊緢澶х殑鍏崇郴銆傝繖浜涘閮ㄧ殑鏉′歡鍖呮嫭鏈夛細(xì) <br />銆銆 錛?CPU--CPU 璧勬簮鐨勪笉瓚充護(hù)鏌ヨ鍙樻參銆傚綋鏌ヨ瓚呰繃浜?Oracle 鏈嶅姟鍣ㄧ殑 CPU 鎬ц兘鏃訛紝浣犵殑鏁版嵁搴撴ц兘灝卞彈鍒?CPU 鐨勯檺鍒躲?<br />銆銆 錛庡唴瀛?-- 鍙敤浜?Oralce 鐨勫唴瀛樻暟閲忎篃浼?xì)濯?jiǎng)鍝?SQL 鐨勬ц兘錛岀壒鍒槸鍦ㄦ暟鎹紦鍐插拰鍐呭瓨鎺掑簭鏂歸潰銆?<br />銆銆 錛庣綉緇?-- 澶ч噺鐨?Net8 閫氫俊浠?SQL 鐨勬ц兘鍙樻參銆?<br />銆銆 璁稿鏂版墜閮介敊璇殑璁や負(fù)搴旇棣栧厛璋冩暣 Oracle 鏁版嵁搴擄紝鑰屼笉鏄厛紜澶栭儴璧勬簮鏄惁瓚沖銆傚疄闄呬笂錛屽鏋滃閮ㄧ幆澧冨嚭鐜扮摱棰堬紝鍐嶅鐨?Oracle 璋冩暣閮芥槸娌℃湁甯姪鐨勩?<br />銆銆 鍦ㄦ鏌?Oracle 鐨勫閮ㄧ幆澧冩椂錛屾湁涓や釜鏂歸潰鏄渶瑕佹敞鎰忕殑錛?<br />銆銆1 銆佸綋榪愯闃熷垪鐨勬暟鐩秴榪囨湇鍔″櫒鐨?CPU 鏁伴噺鏃訛紝鏈嶅姟鍣ㄧ殑鎬ц兘灝變細(xì)鍙楀埌 CPU 鐨勯檺鍒躲傝ˉ鏁戠殑鏂規(guī)硶鏄負(fù)鏈嶅姟鍣ㄥ鍔犻澶栫殑 CPU 鎴栬呭叧闂渶瑕佸緢澶氬鐞嗚祫婧愮殑緇勪歡錛屼緥濡?Oracle Parallel Query 銆?<br />銆銆2 銆佸唴瀛樺垎欏點(diǎn)傚綋鍐呭瓨鍒嗛〉鏃訛紝鍐呭瓨瀹歸噺宸茬粡涓嶈凍錛岃屽唴瀛橀〉鏄笌紓佺洏?shù)笂鐨勪氦鎹㈠岠櫩涜浜や簰鐨勩傝ˉ鏁戠殑鏂規(guī)硶鏄鍔犳洿澶氱殑鍐呭瓨錛屽噺灝?Oracle SGA 鐨勫ぇ灝忥紝鎴栬呭叧闂?Oracle 鐨勫綰跨▼鏈嶅姟鍣ㄣ?<br />銆銆 鍙互浣跨敤鍚勭鏍囧噯鐨勬湇鍔″櫒宸ュ叿鏉ュ緱鍒版湇鍔″櫒鐨勭粺璁℃暟鎹紝渚嬪 vmstat,glance,top 鍜?sar 銆?DBA 鐨勭洰鏍囨槸紜繚鏁版嵁搴撴湇鍔″櫒鎷ユ湁瓚沖鐨?CPU 鍜屽唴瀛樿祫婧愭潵澶勭悊 Oracle 鐨勮姹傘?<br />銆銆 浠ヤ笅璁╂垜浠潵鐪嬩竴涓?Oracle 鐨?row-resequencing 鏄浣曡兘澶熸瀬澶у湴鍑忓皯紓佺洏 I/O 鐨勩?<br /><br />銆銆Row-resequencing 錛堣鐨勯噸鏂版帓搴忥級(jí) <br />銆銆 <br />銆銆灝辮薄鎴戜滑涓婇潰鎻愬埌鐨勶紝鏈夌粡楠岀殑 Oracle DBA 閮界煡閬?I/O 鏄搷搴旀椂闂寸殑鏈澶х粍鎴愰儴鍒嗐傚叾涓鐩?I/O 鐗瑰埆鍘夊錛屽洜涓哄綋 Oracle 鐢辯鐩樹(shù)笂鐨勪竴涓暟鎹枃浠跺緱鍒頒竴涓暟鎹潡鏃訛紝璇葷殑榪涚▼灝卞繀欏葷瓑寰呯墿鐞?I/O 鎿嶄綔瀹屾垚銆傜鐩樻搷浣滆姣旀暟鎹紦鍐叉參 10,000 鍊嶃傚洜姝わ紝濡傛灉鍙互浠?I/O 鏈灝忓寲錛屾垨鑰呭噺灝戠敱浜庣鐩樹(shù)笂鐨勬枃浠剁珵浜夎屽甫鏉ョ殑鐡墮錛屽氨鍙互澶уぇ鍦版敼鍠?Oracle 鏁版嵁搴撶殑鎬ц兘銆?<br />銆銆 濡傛灉緋葷粺鍝嶅簲寰堟參錛岄氳繃鍑忓皯紓佺洏 I/O 灝卞彲浠ユ湁涓涓緢蹇殑鏀瑰杽銆傚鏋滃湪涓涓簨鍔′腑閫氳繃鎸変竴瀹氱殑鑼冨洿鎼滅儲(chǔ) primary-key 绱㈠紩鏉ヨ闂〃錛岄偅涔堥噸鏂頒互 CTAS 鐨勬柟娉曠粍緇囪〃灝嗘槸浣犲噺灝?I/O 鐨勯瑕佺瓥鐣ャ傞氳繃鍦ㄧ墿鐞嗕笂灝嗚鎺掑簭涓哄拰 primary-key 绱㈠紩涓鏍風(fēng)殑欏哄簭錛屽氨鍙互鍔犲揩鑾峰緱鏁版嵁鐨勯熷害銆?<br />銆銆 灝辮薄紓佺洏鐨勮礋杞藉鉤琛′竴鏍鳳紝琛岀殑閲嶆柊鎺掑簭涔熸槸寰堢畝鍗曠殑錛岃屼笖涔熷緢蹇傞氳繃涓庡叾瀹冪殑 DBA 綆＄悊鎶宸т竴璧蜂嬌鐢紝灝卞彲浠ュ湪楂?I/O 鐨勭郴緇熶腑澶уぇ鍦板噺灝戝搷搴旂殑鏃墮棿銆?<br />銆銆 鍦ㄩ珮瀹歸噺鐨勫湪綰夸簨鍔″鐞嗙幆澧冧腑錛?online transaction processing 錛?OLTP 錛夛紝鏁版嵁鏄敱涓涓?primary 绱㈠紩寰楀埌鐨勶紝閲嶆柊鎺掑簭琛ㄦ牸鐨勮灝卞彲浠ヤ護(hù)榪炵畫(huà)鍧楃殑欏哄簭鍜屽畠浠殑 primary 绱㈠紩涓鏍鳳紝榪欐牱灝卞彲浠ュ湪绱㈠紩椹卞姩鐨勮〃鏍兼煡璇腑錛屽噺灝戠墿鐞?I/O 騫朵笖鏀瑰杽鍝嶅簲鏃墮棿銆傝繖涓妧宸т粎鍦ㄥ簲鐢ㄩ夋嫨澶氳鐨勬椂鍊欐湁鐢紝鎴栬呭湪浣跨敤绱㈠紩鑼冨洿鎼滅儲(chǔ)鍜屽簲鐢ㄥ彂鍑哄涓煡璇㈡潵寰楀埌榪炵畫(huà)鐨?key 鏃舵湁鏁堛傚浜庨殢鏈虹殑鍞竴 primary-key 錛堜富閿級(jí)鐨勮闂皢涓嶄細(xì)鐢辮閲嶆柊鎺掑簭涓緱鍒板ソ澶勩?<br />銆銆 璁╂垜浠湅涓涓嬪畠鏄浣曞伐浣滅殑銆傝冭檻浠ヤ笅鐨勪竴涓?SQL 鐨勬煡璇紝瀹冧嬌鐢ㄤ竴涓儲(chǔ)寮曟潵寰楀埌 100 琛岋細(xì) <br />selectsalaryfromemployeewherelast_name like 'B%'; <br />榪欎釜鏌ヨ灝嗕細(xì)浣跨敤 last_name_index 錛屾悳绱㈠叾涓殑姣忎竴琛屾潵寰楀埌鐩爣琛屻傝繖涓煡璇㈠皢浼?xì)鑷碁畱鋴社?100 嬈＄墿鐞嗙鐩樼殑璇誨彇錛屽洜涓?employee 鐨勮瀛樻斁鍦ㄤ笉鍚岀殑鏁版嵁鍧椾腑銆?<br />銆銆 涓嶈繃錛屽鏋滆〃涓殑琛屽凡緇忛噸鏂版帓搴忎負(fù)鍜?last_name_index 鐨勪竴鏍鳳紝鍚屾牱鐨勬煡璇㈠張浼?xì)鎬庢牱澶勭悊鍛紵鎴戜滑鍙互鐪嬪埌榪欎釜鏌ヨ鍙渶瑕佷笁嬈＄殑紓佺洏 I/O 灝辮瀹屽叏閮?100 涓憳宸ョ殑璧勬枡錛堜竴嬈＄敤浣滅儲(chǔ)寮曠殑璇誨彇錛屼袱嬈＄敤浣滄暟鎹潡鐨勮鍙栵級(jí)錛屽噺灝戜簡(jiǎn) 97 嬈＄殑鍧楄鍙栥?<br />銆銆 閲嶆柊鎺掑簭甯︽潵鐨勬ц兘鏀瑰杽鐨勭▼搴﹀湪浜庡湪浣犲紑濮嬬殑鏃跺欒鐨勪貢搴忔у浣曪紝浠ュ強(qiáng)浣犻渶瑕佺敱搴忓垪涓闂灝戣銆傝嚦浜庝竴涓〃涓殑琛屼笌绱㈠紩鐨勬帓搴忛敭鐨勫尮閰嶇▼搴︼紝鍙互鏌ョ湅鏁版嵁瀛楀吀涓殑 dba_indexes 鍜?dba_tables 瑙嗗浘寰楀埌銆?<br />銆銆 鍦?dba_indexes 鐨勮鍥句腑錛屾煡鐪?clustering_factor 鍒椼傚鏋?clustering_factor 鐨勫煎拰琛ㄤ腑鐨勫潡鏁扮洰澶ц嚧涓鏍鳳紝閭ｄ箞浣犵殑琛ㄥ拰绱㈠紩鐨勯『搴忔槸涓鏍風(fēng)殑銆備笉榪囷紝濡傛灉 clustering_factor 鐨勫兼帴榪戣〃涓殑琛屾暟鐩紝閭ｅ氨琛ㄦ槑琛ㄦ牸涓殑琛屽拰绱㈠紩鐨勯『搴忔槸涓嶄竴鏍風(fēng)殑銆?<br />銆銆 琛岄噸鏂版帓搴忕殑浣滅敤鏄笉鍙互灝忕湅鐨勩傚湪闇瑕佽繘琛屽ぇ鑼冨洿鐨勭儲(chǔ)寮曟悳绱㈢殑澶ц〃涓紝琛岄噸鏂版帓搴忓彲浠ヤ護(hù)鏌ヨ鐨勬ц兘鎻愰珮?shù)笁鍊嶃?<br />銆銆 涓鏃︿綘宸茬粡鍐沖畾閲嶆柊鎺掑簭琛ㄤ腑鐨勮錛屼綘鍙互浣跨敤浠ヤ笅鐨勫伐鍏蜂箣涓鏉ラ噸鏂扮粍緇囪〃鏍箋?<br />銆銆. 浣跨敤 Oracle 鐨?Create Table As Select (CTAS) 璇硶鏉ユ嫹璐濊〃鏍?<br />銆銆. Oracle9i 鑷甫鐨勮〃鏍奸噸鏂扮粍緇囧伐鍏?<br />銆銆<br />銆銆 浠ヤ笅錛屾垜浠潵鐪嬩互涓?SQL 璇彞鐨勮皟浼樸?<br /><br />銆銆SQL 璋冧紭 <br />銆銆Oracle 鐨?SQL 璋冧紭鏄竴涓鏉傜殑涓婚錛岀敋鑷蟲(chóng)槸闇瑕佹暣鏈功鏉ヤ粙緇?Oracle SQL 璋冧紭鐨勭粏寰樊鍒備笉榪囨湁涓浜涘熀鏈殑瑙勫垯鏄瘡涓?Oracle DBA 閮介渶瑕佽窡浠庣殑錛岃繖浜涜鍒欏彲浠ユ敼鍠勪粬浠郴緇熺殑鎬ц兘銆?SQL 璋冧紭鐨勭洰鏍囨槸綆鍗曠殑錛?<br />銆銆. 娑堥櫎涓嶅繀瑕佺殑澶ц〃鍏ㄨ〃鎼滅儲(chǔ)錛氫笉蹇呰鐨勫叏琛ㄦ悳绱㈠鑷村ぇ閲忎笉蹇呰鐨?I/O 錛屼粠鑰屾嫋鎱㈡暣涓暟鎹簱鐨勬ц兘銆傝皟浼樹(shù)笓瀹墮鍏堜細(xì)鏍規(guī)嵁鏌ヨ榪斿洖鐨勮鏁扮洰鏉ヨ瘎浠?SQL 銆傚湪涓涓湁搴忕殑琛ㄤ腑錛屽鏋滄煡璇㈣繑鍥炲皯浜?40% 鐨勮錛屾垨鑰呭湪涓涓棤搴忕殑琛ㄤ腑錛岃繑鍥炲皯浜?7% 鐨勮錛岄偅涔堣繖涓煡璇㈤兘鍙互璋冩暣涓轟嬌鐢ㄤ竴涓儲(chǔ)寮曟潵浠ｆ浛鍏ㄨ〃鎼滅儲(chǔ)銆傚浜庝笉蹇呰鐨勫叏琛ㄦ悳绱㈡潵璇達(dá)紝鏈甯歌鐨勮皟浼樻柟娉曟槸澧炲姞绱㈠紩銆傚彲浠ュ湪琛ㄤ腑鍔犲叆鏍囧噯鐨?B 鏍?wèi)鐑?chǔ)寮曪紝涔熷彲浠ュ姞鍏?bitmap 鍜屽熀浜庡嚱鏁扮殑绱㈠紩銆傝鍐沖畾鏄惁娑堥櫎涓涓叏琛ㄦ悳绱紝浣犲彲浠ヤ粩緇嗘鏌ョ儲(chǔ)寮曟悳绱㈢殑 I/O 寮閿鍜屽叏琛ㄦ悳绱㈢殑寮閿錛屽畠浠殑寮閿鍜屾暟鎹潡鐨勮鍙栧拰鍙兘鐨勫茍琛屾墽琛屾湁鍏籌紝騫跺皢涓よ呬綔瀵規(guī)瘮銆傚湪涓浜涙儏鍐典笅錛屼竴浜涗笉蹇呰鐨勫叏琛ㄦ悳绱㈢殑娑堥櫎鍙互閫氳繃寮哄埗浣跨敤涓涓?index 鏉ヨ揪鍒幫紝鍙渶瑕佸湪 SQL 璇彞涓姞鍏ヤ竴涓儲(chǔ)寮曠殑鎻愮ず灝卞彲浠ヤ簡(jiǎn)銆?<br />銆銆. 鍦ㄥ叏琛ㄦ悳绱㈡槸涓涓渶蹇殑璁塊棶鏂規(guī)硶鏃訛紝灝嗗皬琛ㄧ殑鍏ㄨ〃鎼滅儲(chǔ)鏀懼埌緙撳瓨?shù)腑锛岃皟浼樹(shù)笓瀹跺簲璇ゼ嫯淇濇湁涓涓笓闂ㄧ殑鏁版嵁緙撳啿鐢ㄤ綔琛岀紦鍐層傚湪 Oracle7 涓紝浣犲彲浠ヤ嬌鐢?alter table xxx cache 璇彞錛屽湪 Oracle8 鎴栦互涓婏紝灝忚〃鍙互琚己鍒朵負(fù)鏀懼埌 KEEP 姹犱腑緙撳啿銆?<br />銆銆. 紜繚鏈浼樼殑绱㈠紩浣跨敤 錛氬浜庢敼鍠勬煡璇㈢殑閫熷害錛岃繖鏄壒鍒噸瑕佺殑銆傛湁鏃?Oracle 鍙互閫夋嫨澶氫釜绱㈠紩鏉ヨ繘琛屾煡璇紝璋冧紭?shù)笓瀹跺繀椤粙個(gè)鏌ユ瘡涓儲(chǔ)寮曞茍涓旂‘淇?Oracle 浣跨敤姝ｇ‘鐨勭儲(chǔ)寮曘傚畠榪樺寘鎷?bitmap 鍜屽熀浜庡嚱鏁扮殑绱㈠紩鐨勪嬌鐢ㄣ?<br />銆銆. 紜繚鏈浼樼殑 JOIN 鎿嶄綔錛氭湁浜涙煡璇嬌鐢?NESTED LOOP join 蹇竴浜涳紝鏈変簺鍒欐槸 HASH join 蹇竴浜涳紝鍙﹀涓浜涘垯鏄?sort-merge join 鏇村揩銆?<br />銆銆 榪欎簺瑙勫垯鐪嬫潵綆鍗曪紝涓嶈繃瀹冧滑鍗?SQL 璋冧紭?shù)徽d姟鐨?90% 錛屽茍涓斿畠浠篃鏃犻渶瀹屽叏鎳傚緱 Oracle SQL 鐨勫唴閮ㄨ繍浣溿備互涓嬫垜浠潵綆鍗曟瑙堜互涓?Oracle SQL 鐨勪紭鍖栥?<br />銆銆 鎴戜滑棣栧厛綆瑕佹煡鐪?Oracle 鐨勬帓搴忥紝騫朵笖鐪嬩竴鐪嬫帓搴忔搷浣滄槸濡備綍褰卞搷鎬ц兘鐨勩?<br /><br />銆銆 璋冩暣 Oracle 鐨勬帓搴忔搷浣?<br />銆銆 鎺掑簭鏄?SQL 璇硶涓竴涓皬鐨勬柟闈紝浣嗗緢閲嶈錛屽湪 Oracle 鐨勮皟鏁翠腑錛屽畠甯稿父琚拷鐣ャ傚綋浣跨敤 create index 銆?ORDER BY 鎴栬?GROUP BY 鐨勮鍙ユ椂錛?Oracle 鏁版嵁搴撳皢浼?xì)鑷姩鎵ц鎺掑簭鐨勬搷浣溿傞氬父錛屽湪浠ヤ笅鐨勬儏鍐典笅 Oracle 浼?xì)杩涜鎺掑簭鐨勬搷浣滃Q?<br />銆銆 浣跨敤 Order by 鐨?SQL 璇彞 <br />銆銆 浣跨敤 Group by 鐨?SQL 璇彞 <br />銆銆 鍦ㄥ垱寤虹儲(chǔ)寮曠殑鏃跺?<br />銆銆 榪涜 table join 鏃訛紝鐢變簬鐜版湁绱㈠紩鐨勪笉瓚寵屽鑷?SQL 浼樺寲鍣ㄨ皟鐢?MERGE SORT <br />銆銆 褰撲笌 Oracle 寤虹珛璧蜂竴涓?session 鏃訛紝鍦ㄥ唴瀛樹(shù)腑灝變細(xì)涓鴻 session 鍒嗛厤涓涓鏈夌殑鎺掑簭鍖哄煙銆傚鏋滆榪炴帴鏄竴涓笓鐢ㄧ殑榪炴帴 (dedicated connection) 錛岄偅涔堝氨浼?xì)鏍规?init.ora 涓?sort_area_size 鍙傛暟鐨勫ぇ灝忓湪鍐呭瓨?shù)腑鍒嗛厤涓涓?Program Global Area (PGA) 銆傚鏋滆繛鎺ユ槸閫氳繃澶氱嚎紼嬫湇鍔″櫒寤虹珛鐨勶紝閭ｄ箞鎺掑簭鐨勭┖闂村氨鍦?large_pool 涓垎閰嶃備笉騫哥殑鏄紝瀵逛簬鎵鏈夌殑 session 錛岀敤鍋氭帓搴忕殑鍐呭瓨閲忛兘蹇呴』鏄竴鏍風(fēng)殑錛屾垜浠笉鑳戒負(fù)闇瑕佹洿澶ф帓搴忕殑鎿嶄綔鍒嗛厤棰濆鐨勬帓搴忓尯鍩熴傚洜姝わ紝璁捐鑰呭繀欏諱綔鍑轟竴涓鉤琛★紝鍦ㄥ垎閰嶈凍澶熺殑鎺掑簭鍖哄煙浠ラ伩鍏嶅彂鐢熷ぇ鐨勬帓搴忎換鍔℃椂鍑虹幇紓佺洏鎺掑簭錛?disk sorts 錛夌殑鍚屾椂錛屽浜庨偅浜涘茍涓嶉渶瑕佽繘琛屽緢澶ф帓搴忕殑浠誨姟錛屽氨浼?xì)鍑虹庮C竴浜涙氮璐廣傚綋鐒?dòng)灱屽綋鎺掑簭鐨劷I洪棿闇姹傝秴鍑轟簡(jiǎn) sort_area_size 鐨勫ぇ灝忔椂錛岃繖鏃跺皢浼?xì)鍦?TEMP 琛ㄧ┖闂翠腑鍒嗛〉榪涜紓佺洏鎺掑簭銆傜鐩樻帓搴忚姣斿唴瀛樻帓搴忓ぇ姒傛參 14,000 鍊嶃?<br />銆銆 涓婇潰鎴戜滑宸茬粡鎻愬埌錛岀鏈夋帓搴忓尯鍩熺殑澶у皬鏄湁 init.ora 涓殑 sort_area_size 鍙傛暟鍐沖畾鐨勩傛瘡涓帓搴忔墍鍗犵敤鐨勫ぇ灝忕敱 init.ora 涓殑 sort_area_retained_size 鍙傛暟鍐沖畾銆傚綋鎺掑簭涓嶈兘鍦ㄥ垎閰嶇殑絀洪棿涓畬鎴愭椂錛屽氨浼?xì)鋴社敤纾佺洏鎺掑簭鐨勬柟寮忓Q屽嵆鍦?Oracle 瀹炰緥涓殑涓存椂琛ㄧ┖闂翠腑榪涜銆?<br />銆銆 紓佺洏鎺掑簭鐨勫紑閿鏄緢澶х殑錛屾湁鍑犱釜鏂歸潰鐨勫師鍥犮傞鍏堬紝鍜屽唴瀛樻帓搴忕浉姣旇緝錛屽畠浠壒鍒參錛涜屼笖紓佺洏鎺掑簭浼?xì)娑堣椾復(fù)鏃惰〃絀洪棿涓殑璧勬簮銆?Oracle 榪樺繀欏誨垎閰嶇紦鍐叉睜鍧楁潵淇濇寔涓存椂琛ㄧ┖闂翠腑鐨勫潡銆傛棤璁轟粈涔堟椂鍊欙紝鍐呭瓨鎺掑簭閮芥瘮紓佺洏鎺掑簭濂斤紝紓佺洏鎺掑簭灝嗕細(xì)浠や換鍔″彉鎱紝騫朵笖浼?xì)濯?jiǎng)鍝?Oracle 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