浠婂ぉ鍦ㄧ啛鎮(zhèn)夋垜浠殑欏圭洰鐨勬椂鍊欙紝sql涓湅鍒癋ORCE INDEX錛岄錛岄兘涓嶇煡閬撲粈涔堜笢涓滐紝鏈変粈涔堢壒鍒敤澶勫悧錛?鏌ヤ簡涓嬭祫鏂欙紝鍘熸潵鏄繖鏍峰晩錛屽彂鐜頒竴鑸笉鎼炲鏉俿ql錛岃屼笖澶嶆潅sql DBA涔熶笉鍏佽錛屼絾浼樺寲鐨剆ql 榪樻槸鏈夊繀瑕佷簡瑙ｄ笅銆傦紙涓鑸潵璇翠篃涓嶅お浼?xì)鋴社敤锛屾昏DBA pk浜嗭級
涓嬮潰閮ㄥ垎杞細(xì)
瀵逛簬緇忓父浣跨敤oracle鐨勬湅鍙嬪彲鑳界煡閬擄紝oracle鐨刪int鍔熻兘縐嶇被寰堝錛屽浜庝紭鍖杝ql璇彞鎻愪緵浜嗗緢澶氭柟娉曘傚悓鏍鳳紝鍦╩ysql閲岋紝涔熸湁綾諱技鐨刪int鍔熻兘銆備笅闈粙緇嶄竴浜涘父鐢ㄧ殑銆?
1銆傚己鍒剁儲寮?FORCE INDEX
SELECT * FROM TABLE1 FORCE INDEX (FIELD1) …
浠ヤ笂鐨凷QL璇彞鍙嬌鐢ㄥ緩绔嬪湪FIELD1涓婄殑绱㈠紩錛岃屼笉浣跨敤鍏跺畠瀛楁涓婄殑绱㈠紩銆?
2銆傚拷鐣ョ儲寮?IGNORE INDEX
SELECT * FROM TABLE1 IGNORE INDEX (FIELD1, FIELD2) …
鍦ㄤ笂闈㈢殑SQL璇彞涓紝TABLE1琛ㄤ腑FIELD1鍜孎IELD2涓婄殑绱㈠紩涓嶈浣跨敤銆?
3銆傚叧闂煡璇㈢紦鍐?SQL_NO_CACHE
SELECT SQL_NO_CACHE field1, field2 FROM TABLE1;
鏈変竴浜汼QL璇彞闇瑕佸疄鏃跺湴鏌ヨ鏁版嵁錛屾垨鑰呭茍涓嶇粡甯鎬嬌鐢紙鍙兘涓澶╁氨鎵ц涓涓ゆ錛?榪欐牱灝遍渶瑕佹妸緙撳啿鍏充簡,涓嶇榪欐潯SQL璇彞鏄惁琚墽琛岃繃錛屾湇鍔″櫒閮戒笉浼?xì)鍦ň~撳啿鍖轟腑鏌ユ壘錛屾瘡嬈￠兘浼?xì)鎵ц瀹冦?
4銆傚己鍒舵煡璇㈢紦鍐?SQL_CACHE
SELECT SQL_CALHE * FROM TABLE1;
濡傛灉鍦╩y.ini涓殑query_cache_type璁炬垚2錛岃繖鏍峰彧鏈夊湪浣跨敤浜哠QL_CACHE鍚庯紝鎵嶄嬌鐢ㄦ煡璇㈢紦鍐層?
5銆備紭鍏堟搷浣?HIGH_PRIORITY
HIGH_PRIORITY鍙互浣跨敤鍦╯elect鍜宨nsert鎿嶄綔涓紝璁㎝YSQL鐭ラ亾錛岃繖涓搷浣滀紭鍏堣繘琛屻?
SELECT HIGH_PRIORITY * FROM TABLE1;
6銆傛粸鍚庢搷浣?LOW_PRIORITY
LOW_PRIORITY鍙互浣跨敤鍦╥nsert鍜寀pdate鎿嶄綔涓紝璁﹎ysql鐭ラ亾錛岃繖涓搷浣滄粸鍚庛?
update LOW_PRIORITY table1 set field1= where field1= …
7銆傚歡鏃舵彃鍏?INSERT DELAYED
INSERT DELAYED INTO table1 set field1= …
INSERT DELAYED INTO錛屾槸瀹㈡埛绔彁浜ゆ暟鎹粰MySQL錛孧ySQL榪斿洖OK鐘舵佺粰瀹㈡埛绔傝岃繖鏄茍涓嶆槸宸茬粡灝嗘暟鎹彃鍏ヨ〃錛岃屾槸瀛樺偍鍦ㄥ唴瀛橀噷闈㈢瓑寰呮帓闃熴傚綋mysql鏈夌┖浣欐椂錛屽啀鎻掑叆銆傚彟涓涓噸瑕佺殑濂藉鏄紝鏉ヨ嚜璁稿瀹㈡埛绔殑鎻掑叆琚泦涓湪涓璧鳳紝騫惰緙栧啓鍏ヤ竴涓潡銆傝繖姣旀墽琛岃澶氱嫭绔嬬殑鎻掑叆瑕佸揩寰堝銆傚潖澶勬槸錛屼笉鑳借繑鍥炶嚜鍔ㄩ掑鐨処D錛屼互鍙婄郴緇熷穿婧冩椂錛孧ySQL榪樻病鏈夋潵寰楀強鎻掑叆鏁版嵁鐨勮瘽錛岃繖浜涙暟鎹皢浼?xì)涓㈠け銆?
8 銆傚己鍒惰繛鎺ラ『搴?STRAIGHT_JOIN
SELECT TABLE1.FIELD1, TABLE2.FIELD2 FROM TABLE1 STRAIGHT_JOIN TABLE2 WHERE …
鐢變笂闈㈢殑SQL璇彞鍙煡錛岄氳繃STRAIGHT_JOIN寮鴻揩MySQL鎸塗ABLE1銆乀ABLE2鐨勯『搴忚繛鎺ヨ〃銆傚鏋滀綘璁や負(fù)鎸夎嚜宸辯殑欏哄簭姣擬ySQL鎺ㄨ崘鐨勯『搴忚繘琛岃繛鎺ョ殑鏁堢巼楂樼殑璇濓紝灝卞彲浠ラ氳繃STRAIGHT_JOIN鏉ョ‘瀹氳繛鎺ラ『搴忋?
9銆傚己鍒朵嬌鐢ㄤ復(fù)鏃惰〃 SQL_BUFFER_RESULT
SELECT SQL_BUFFER_RESULT * FROM TABLE1 WHERE …
褰撴垜浠煡璇㈢殑緇撴灉闆嗕腑鐨勬暟鎹瘮杈冨鏃訛紝鍙互閫氳繃SQL_BUFFER_RESULT.閫夐」寮哄埗灝嗙粨鏋滈泦鏀懼埌涓存椂琛ㄤ腑錛岃繖鏍峰氨鍙互寰堝揩鍦伴噴鏀綧ySQL鐨勮〃閿侊紙榪欐牱鍏跺畠鐨凷QL璇彞灝卞彲浠ュ榪欎簺璁板綍榪涜鏌ヨ浜嗭級錛屽茍涓斿彲浠ラ暱鏃墮棿鍦頒負(fù)瀹㈡埛绔彁渚涘ぇ璁板綍闆嗐?
10銆傚垎緇勪嬌鐢ㄤ復(fù)鏃惰〃 SQL_BIG_RESULT鍜孲QL_SMALL_RESULT
SELECT SQL_BUFFER_RESULT FIELD1, COUNT(*) FROM TABLE1 GROUP BY FIELD1;
涓鑸敤浜庡垎緇勬垨DISTINCT鍏抽敭瀛楋紝榪欎釜閫夐」閫氱煡MySQL錛屽鏋滄湁蹇呰錛屽氨灝嗘煡璇㈢粨鏋滄斁鍒頒復(fù)鏃惰〃涓紝鐢氳嚦鍦ㄤ復(fù)鏃惰〃涓繘琛屾帓搴忋係QL_SMALL_RESULT姣旇搗SQL_BIG_RESULT宸笉澶氾紝寰堝皯浣跨敤銆?/p>
鎬葷粨濡備笅:
1.#鏄妸浼犲叆鐨勬暟鎹綋浣滃瓧絎︿覆錛屽#user_id_list#浼犲叆鐨勬槸1,2,鍒檚ql璇彞鐢熸垚鏄繖鏍鳳紝in ('1,2') ,褰撶劧涓嶅彲浠?br />
2.$浼犲叆鐨勬暟鎹洿鎺ョ敓鎴愬湪sql閲岋紝濡?user_id_list#浼犲叆鐨勬槸1,2,鍒檚ql璇彞鐢熸垚鏄繖鏍鳳紝in(1,2) 榪欏氨瀵逛簡錛?#160;
3.#鏂瑰紡鑳藉寰堝ぇ紼嬪害闃叉sql娉ㄥ叆錛?#160;
4.$鏂瑰紡鏃犳硶鏂瑰紡sql娉ㄥ叆錛?#160;
5.$鏂瑰紡涓鑸敤浜庝紶鍏ユ暟鎹簱瀵硅薄錛庝緥濡備紶鍏ヨ〃鍚?
6.涓鑸兘鐢?鐨勫氨鍒敤$.
#str# 鍑烘潵鐨勬晥鏋滄槸 'str'
$str$ 鍑烘潵鐨勬晥鏋滄槸 str
鍙﹀ ##鍙兘鐢ㄥ湪鐗瑰畾鐨勫嚑涓湴鏂?$$鍙互鐢ㄥ湪浠諱綍鍦版柟 姣斿 order by $str$
浣犵敋鑷沖彲浠ョ洿鎺ュ啓 $str$ 鎶?order by 榪欎釜瀛椾覆鏀懼湪str閲屼紶榪涙潵
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minvalue 1
maxvalue 9999999999
start with 1
increment by 1
cache 20;
create or replace trigger TR_TB_OA_DUANXIN_ID_INC
declare
tmp NUMBER;
begin
end TR_TB_OA_DUANXIN_ID_INC;
]]>
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銆銆瀹夎SQL Server 2000鐨勬搷浣滅郴緇熸槸Windows 2000 Profession Edition,瀹夎綆浣撲腑鏂囨爣鍑嗙増銆備細(xì)鎻愮ず璇ョ増鏈殑鎿嶄綔緋葷粺涓嶈兘瀹夎鏈嶅姟鍣ㄧ粍浠訛紝鍙兘瀹夎SQL Server 2000涓漢鐗堛備簬鏄鍑猴紝閫夋嫨瀹夎涓漢鐗堛傚嵈鍑虹幇浜嗘柊鐨勯敊璇細(xì) “浠ュ墠鐨勬煇涓▼搴忓畨瑁呭凡鍦ㄥ畨瑁呰綆楁満涓婂垱寤烘寕璧風(fēng)殑鏂囦歡鎿嶄綔銆傝繍琛屽畨瑁呯▼搴忎箣鍓嶅繀欏婚噸鏂板惎鍔ㄨ綆楁満銆?/span> ”銆鎺ョ潃鎸夌収鎻愮ず閲嶅惎璁＄畻鏈猴紝鍐嶅畨瑁咃紝浠嶇劧鍑虹幇鍚屾牱鐨勬彁紺恒傚啀緗戜笂鏌ユ壘鐩稿叧璧勬枡錛屽緱鐭ユ槸瀹夎紼嬪簭鍦ㄥ厛鍓嶇殑瀹夎榪囩▼涓湪緋葷粺娉ㄥ唽琛ㄧ暀涓嬫煇浜涗俊鎭紝瀵艱嚧涓嶈兘瀹夎銆備簬鏄粡榪囧嬈¤瘯錛屽彂鐜板垹闄ゆ帀濡備笅閿間俊鎭嵆鍙畨瑁咃細(xì)鍦ㄨ繍琛岀獥鍙ｈ緭鍏?/span>regedit錛屾墦寮娉ㄥ唽琛ㄧ紪杈戝櫒錛屽湪HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager涓壘鍒?/span>PendingFileRenameOperations錛?/span> 鍒犻櫎璇ラ敭鍊鹼紝鍏抽棴娉ㄥ唽琛ㄧ紪杈戝櫒銆傞噸鏂板畨瑁?/span>SQL Server 2000錛屽搱鍝堬紝涔呰繚鐨勫畨瑁呯晫闈㈢粓浜庢誕鍑烘按闈簡銆?/span>
銆銆榪欎釜閿兼槸瀹夎紼嬪簭鏆傛寕欏圭洰錛屽彧瑕佹壘鍒板搴旂殑搴旂敤紼嬪簭娓呴櫎鎺夊氨琛屼簡銆?/span>
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