锘??xml version="1.0" encoding="utf-8" standalone="yes"?>亚洲午夜理论片在线观看,亚洲18在线天美,亚洲av综合avav中文http://m.tkk7.com/Vincent-chenxj/category/36552.htmlzh-cnTue, 09 Dec 2008 04:18:19 GMTTue, 09 Dec 2008 04:18:19 GMT60- SQL鍩烘湰璇彞http://m.tkk7.com/Vincent-chenxj/articles/245153.htmlVincent-chenVincent-chenTue, 09 Dec 2008 02:02:00 GMThttp://m.tkk7.com/Vincent-chenxj/articles/245153.htmlhttp://m.tkk7.com/Vincent-chenxj/comments/245153.htmlhttp://m.tkk7.com/Vincent-chenxj/articles/245153.html#Feedback0http://m.tkk7.com/Vincent-chenxj/comments/commentRss/245153.htmlhttp://m.tkk7.com/Vincent-chenxj/services/trackbacks/245153.html鎺屾彙SQL鍥涙潯鏈鍩烘湰鐨勬暟鎹搷浣滆鍙ワ細Insert錛孲elect錛孶pdate鍜孌elete銆?br />
銆銆 緇冩帉鎻QL鏄暟鎹簱鐢ㄦ埛鐨勫疂璐佃儲 瀵屻傚湪鏈枃涓紝鎴戜滑灝嗗紩瀵間綘鎺屾彙鍥涙潯鏈鍩烘湰鐨勬暟鎹搷浣滆鍙モ擲QL鐨勬牳蹇冨姛鑳解旀潵渚濇浠嬬粛姣旇緝鎿嶄綔絎︺侀夋嫨鏂█浠ュ強涓夊奸昏緫銆傚綋浣犲畬鎴愯繖浜涘涔犲悗錛屾樉鐒朵綘宸茬粡寮濮嬬畻鏄簿閫歋QL浜嗐?br />
銆銆鍦ㄦ垜浠紑濮嬩箣鍓嶏紝鍏堜嬌鐢–REATE TABLE璇彞鏉ュ垱寤轟竴涓〃錛堝鍥?鎵紺猴級銆侱DL璇彞瀵規暟鎹簱瀵硅薄濡傝〃銆佸垪鍜岃榪涜瀹氫箟銆傚畠浠茍涓嶅琛ㄤ腑鐨勮榪涜澶勭悊錛岃繖鏄洜涓篋DL璇彞騫朵笉澶勭悊鏁版嵁搴撲腑瀹為檯鐨勬暟鎹傝繖浜涘伐浣滅敱鍙︿竴綾籗QL璇彞鈥旀暟鎹搷浣滆璦錛圖ML錛夎鍙ヨ繘琛屽鐞嗐?br />
銆銆SQL涓湁鍥涚鍩烘湰鐨凞ML鎿嶄綔錛欼NSERT錛孲ELECT錛孶PDATE鍜孌ELETE銆傜敱浜庤繖鏄ぇ澶氭暟SQL鐢ㄦ埛緇忓父鐢ㄥ埌鐨勶紝鎴戜滑鏈夊繀瑕佸湪姝ゅ瀹冧滑榪涜涓涓璇存槑銆傚湪鍥?涓垜浠粰鍑轟簡涓涓悕涓篍MPLOYEES鐨勮〃銆傚叾涓殑姣忎竴琛屽搴斾竴涓壒瀹氱殑闆囧憳璁板綍銆傝鐔熸倝榪欏紶琛紝鎴戜滑鍦ㄥ悗闈㈢殑渚嬪瓙涓皢瑕佺敤鍒板畠銆?br />
銆銆INSERT璇彞
銆銆鐢ㄦ埛鍙互鐢↖NSERT璇彞灝嗕竴琛岃褰曟彃鍏ュ埌鎸囧畾鐨勪竴涓〃涓備緥濡傦紝瑕佸皢闆囧憳John Smith鐨勮褰曟彃鍏ュ埌鏈緥鐨勮〃涓紝鍙互浣跨敤濡備笅璇彞錛?br />
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Smith','John','1980-06-10',
銆銆 'Los Angles',16,45000);
銆銆閫氳繃榪欐牱鐨処NSERT璇彞錛岀郴緇熷皢璇曠潃灝嗚繖浜涘煎~鍏ュ埌鐩稿簲鐨勫垪涓傝繖浜涘垪鎸夌収鎴戜滑鍒涘緩琛ㄦ椂瀹氫箟鐨勯『搴忔帓鍒椼傚湪鏈緥涓紝絎竴涓?#8220;Smith”灝嗗~鍒扮涓涓垪LAST_NAME涓紱絎簩涓?#8220;John”灝嗗~鍒扮浜屽垪FIRST_NAME涓?#8230;…浠ユ綾繪帹銆?br />
銆銆鎴戜滑璇磋繃緋葷粺浼?#8220;璇曠潃”灝嗗煎~鍏ワ紝闄や簡鎵ц瑙勫垯涔嬪瀹冭繕瑕佽繘琛岀被鍨嬫鏌ャ傚鏋滅被鍨嬩笉絎︼紙濡傚皢涓涓瓧絎︿覆濉叆鍒扮被鍨嬩負鏁板瓧鐨勫垪涓級錛岀郴緇熷皢鎷掔粷榪欎竴嬈℃搷浣滃茍榪斿洖涓涓敊璇俊鎭?br />
銆銆濡傛灉SQL鎷掔粷浜嗕綘鎵濉叆鐨勪竴鍒楀鹼紝璇彞涓叾浠栧悇鍒楃殑鍊間篃涓嶄細濉叆銆傝繖鏄洜涓篠QL鎻愪緵瀵逛簨鍔$殑鏀寔銆備竴嬈′簨鍔″皢鏁版嵁搴撲粠涓縐嶄竴鑷存ц漿縐誨埌鍙︿竴縐嶄竴鑷存с傚鏋滀簨鍔$殑鏌愪竴閮ㄥ垎澶辮觸錛屽垯鏁翠釜浜嬪姟閮戒細澶辮觸錛岀郴緇熷皢浼氳鎭㈠錛堟垨縐頒箣涓哄洖閫錛夊埌姝や簨鍔′箣鍓嶇殑鐘舵併?br />
銆銆 鍥炲埌鍘熸潵鐨処NSERT鐨勪緥瀛愶紝璇鋒敞鎰忔墍鏈夌殑鏁村艦鍗佽繘鍒舵暟閮戒笉闇瑕佺敤鍗曞紩鍙峰紩璧鋒潵錛岃屽瓧絎︿覆鍜屾棩鏈熺被鍨嬬殑鍊奸兘瑕佺敤鍗曞紩鍙鋒潵鍖哄埆銆備負浜嗗鍔犲彲璇繪ц屽湪鏁板瓧闂存彃鍏ラ楀彿灝嗕細寮曡搗閿欒銆傝浣忥紝鍦⊿QL涓楀彿鏄厓绱犵殑鍒嗛殧絎︺?br />
銆銆鍚屾牱瑕佹敞鎰忚緭鍏ユ枃瀛楀兼椂瑕佷嬌鐢ㄥ崟寮曞彿銆傚弻寮曞彿鐢ㄦ潵灝佽闄愮晫鏍囪瘑絎︺?br />
銆銆瀵逛簬鏃ユ湡綾誨瀷錛屾垜浠繀欏諱嬌鐢⊿QL鏍囧噯鏃ユ湡鏍煎紡錛坹yyy-mm-dd錛夛紝浣嗘槸鍦ㄧ郴緇熶腑鍙互榪涜瀹氫箟錛屼互鎺ュ彈鍏朵粬鐨勬牸寮忋傚綋鐒訛紝2000騫翠復榪戯紝璇蜂綘鏈濂借繕鏄嬌鐢ㄥ洓浣嶆潵琛ㄧず騫翠喚銆?br />
銆銆鏃㈢劧浣犲凡緇忕悊瑙d簡INSERT璇彞鏄庢牱宸ヤ綔鐨勪簡錛岃鎴戜滑杞埌EMPLOYEES琛ㄤ腑鐨勫叾浠栭儴鍒嗭細
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Bunyan','Paul','1970-07-04',
銆銆 'Boston',12,70000);
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('John','Adams','1992-01-21',
銆銆 'Boston',20,100000);
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Smith','Pocahontas','1976-04-06',
銆銆 'Los Angles',12,100000);
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Smith','Bessie','1940-05-02',
銆銆 'Boston',5,200000);
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Jones','Davy','1970-10-10',
銆銆 'Boston',8,45000);
銆銆INSERT INTO EMPLOYEES VALUES
銆銆 ('Jones','Indiana','1992-02-01',
銆銆 'Chicago',NULL,NULL);
銆銆鍦ㄦ渶鍚庝竴欏逛腑錛屾垜浠笉鐭ラ亾Jones鍏堢敓鐨勫伐钖駭鍒拰騫磋柂錛屾墍浠ユ垜浠緭鍏ULL錛堜笉瑕佸紩鍙鳳級銆侼ULL鏄疭QL涓殑涓縐嶇壒孌婃儏鍐碉紝鎴戜滑浠ュ悗灝嗚繘琛岃緇嗙殑璁ㄨ銆傜幇鍦ㄦ垜浠彧闇璁や負NULL琛ㄧず涓縐嶆湭鐭ョ殑鍊箋?br />
銆銆鏈夋椂錛屽儚鎴戜滑鍒氭墠鎵璁ㄨ鐨勬儏鍐碉紝鎴戜滑鍙兘甯屾湜瀵規煇涓浜涜屼笉鏄叏閮ㄧ殑鍒楄繘琛岃祴鍊箋傞櫎浜嗗瑕佺渷鐣ョ殑鍒楄緭鍏ULL澶栵紝榪樺彲浠ラ噰鐢ㄥ彟澶栦竴縐岻NSERT璇彞錛屽涓嬶細
銆銆INSERT INTO EMPLOYEES(
銆銆 FIRST_NAME, LAST_NAME,
銆銆 HIRE_DATE, BRANCH_OFFICE)
銆銆VALUE(
銆銆 'Indiana','Jones',
銆銆 '1992-02-01','Indianapolis');
銆銆榪欐牱錛屾垜浠厛鍦ㄨ〃鍚嶄箣鍚庡垪鍑轟竴緋誨垪鍒楀悕銆傛湭鍒楀嚭鐨勫垪涓皢鑷姩濉叆緙虹渷鍊鹼紝濡傛灉娌℃湁璁劇疆緙虹渷鍊煎垯濉叆NULL銆傝娉ㄦ剰鎴戜滑鏀瑰彉浜嗗垪鐨勯『搴忥紝鑰屽肩殑欏哄簭瑕佸搴旀柊鐨勫垪鐨勯『搴忋傚鏋滆璇彞涓渷鐣ヤ簡FIRST_NAME鍜孡AST_NAME欏癸紙榪欎袱欏硅瀹氫笉鑳戒負絀猴級錛孲QL鎿嶄綔灝嗗け璐ャ?br />
銆銆璁╂垜浠潵鐪嬩竴鐪嬩笂榪癐NSERT璇彞鐨勮娉曞浘錛?br />
銆銆INSERT INTO table
銆銆 [(column { ,column})]
銆銆VALUES
銆銆 (columnvalue [{,columnvalue}]);
銆銆鍜屽墠涓綃囨枃绔犱腑涓鏍鳳紝鎴戜滑鐢ㄦ柟鎷彿鏉ヨ〃紺哄彲閫夐」錛屽ぇ鎷彿琛ㄧず鍙互閲嶅浠繪剰嬈℃暟鐨勯」錛堜笉鑳藉湪瀹為檯鐨凷QL璇彞涓嬌鐢ㄨ繖浜涚壒孌婂瓧絎︼級銆俈ALUE瀛愬彞鍜屽彲閫夌殑鍒楀悕鍒楄〃涓繀欏諱嬌鐢ㄥ渾鎷彿銆?br />
銆銆SELECT璇彞
銆銆SELECT璇彞鍙互浠庝竴涓垨澶氫釜琛ㄤ腑閫夊彇鐗瑰畾鐨勮鍜屽垪銆傚洜涓烘煡璇㈠拰媯绱㈡暟鎹槸鏁版嵁搴撶鐞嗕腑鏈閲嶈鐨勫姛鑳斤紝鎵浠ELECT璇彞鍦⊿QL涓槸宸ヤ綔閲忔渶澶х殑閮ㄥ垎銆傚疄闄呬笂錛屼粎浠呮槸璁塊棶鏁版嵁搴撴潵鍒嗘瀽鏁版嵁騫剁敓鎴愭姤琛ㄧ殑浜哄彲浠ュ鍏朵粬SQL璇彞涓紿嶄笉閫氥?br />
銆銆SELECT璇彞鐨勭粨鏋滈氬父鏄敓鎴愬彟澶栦竴涓〃銆傚湪鎵ц榪囩▼涓郴緇熸牴鎹敤鎴風殑鏍囧噯浠庢暟鎹簱涓夊嚭鍖歸厤鐨勮鍜屽垪錛屽茍灝嗙粨鏋滄斁鍒頒復鏃剁殑琛ㄤ腑銆傚湪鐩存帴SQL錛坉irect SQL錛変腑錛屽畠灝嗙粨鏋滄樉紺哄湪緇堢鐨勬樉紺哄睆涓婏紝鎴栬呭皢緇撴灉閫佸埌鎵撳嵃鏈烘垨鏂囦歡涓備篃鍙互緇撳悎鍏朵粬SQL璇彞鏉ュ皢緇撴灉鏀懼埌涓涓凡鐭ュ悕縐扮殑琛ㄤ腑銆?br />
銆銆SELECT璇彞鍔熻兘寮哄ぇ銆傝櫧鐒惰〃闈笂鐪嬫潵瀹冨彧鐢ㄦ潵瀹屾垚鏈枃絎竴閮ㄥ垎涓彁鍒扮殑鍏崇郴浠f暟榪愮畻“閫夋嫨”錛堟垨縐?#8220;闄愬埗”錛夛紝浣嗗疄闄呬笂瀹冧篃鍙互瀹屾垚鍏朵粬涓ょ鍏崇郴榪愮畻鈥?#8220;鎶曞獎”鍜?#8220;榪炴帴”錛孲ELECT璇彞榪樺彲浠ュ畬鎴愯仛鍚堣綆楀茍瀵規暟鎹繘琛屾帓搴忋?br />
銆銆SELECT璇彞鏈綆鍗曠殑璇硶濡備笅錛?br />
銆銆SELECT columns FROM tables;
銆銆褰撴垜浠互榪欑褰㈠紡鎵ц涓鏉ELECT璇彞鏃訛紝緋葷粺榪斿洖鐢辨墍閫夋嫨鐨勫垪浠ュ強鐢ㄦ埛閫夋嫨鐨勮〃涓墍鏈夋寚瀹氱殑琛岀粍鎴愮殑涓涓粨鏋滆〃銆傝繖灝辨槸瀹炵幇鍏崇郴鎶曞獎榪愮畻鐨勪竴涓艦寮忋?br />
銆銆璁╂垜浠湅涓涓嬩嬌鐢ㄥ浘1涓璄MPLOYEES琛ㄧ殑涓浜涗緥瀛愶紙榪欎釜琛ㄦ槸鎴戜滑浠ュ悗鎵鏈塖ELECT璇彞瀹炰緥閮借浣跨敤鐨勩傝屾垜浠湪鍥?鍜屽浘3涓粰鍑轟簡鏌ヨ鐨勫疄闄呯粨鏋溿傛垜浠皢鍦ㄥ叾浠栫殑渚嬪瓙涓嬌鐢ㄨ繖浜涚粨鏋滐級銆?br />
銆銆鍋囪浣犳兂鏌ョ湅闆囧憳宸ヤ綔閮ㄩ棬鐨勫垪琛ㄣ傞偅涓嬮潰灝辨槸浣犳墍闇瑕佺紪鍐欑殑SQL鏌ヨ錛?br />
銆銆SELECT BRANCH_OFFICE FROM EMPLOYEES;
銆銆浠ヤ笂SELECT璇彞鐨勬墽琛屽皢浜х敓濡傚浘2涓〃2鎵紺虹殑緇撴灉銆?br />
銆銆鐢變簬鎴戜滑鍦⊿ELECT璇彞涓彧鎸囧畾浜嗕竴涓垪錛屾墍浠ユ垜浠殑緇撴灉琛ㄤ腑涔熷彧鏈変竴涓垪銆傛敞鎰忕粨鏋滆〃涓叿鏈夐噸澶嶇殑琛岋紝榪欐槸鍥犱負鏈夊涓泧鍛樺湪鍚屼竴閮ㄩ棬宸ヤ綔錛堣浣廠QL浠庢墍閫夌殑鎵鏈夎涓皢鍊艱繑鍥烇級銆傝娑堥櫎緇撴灉涓殑閲嶅琛岋紝鍙鍦⊿ELECT璇彞涓姞涓奃ISTINCT瀛愬彞錛?br />
銆銆SELECT DISTINCT BRANCH_OFFICE
銆銆FROM EMPLOYEES;
銆銆榪欐鏌ヨ鐨勭粨鏋滃琛?鎵紺恒?br />
銆銆鐜板湪宸茬粡娑堥櫎浜嗛噸澶嶇殑琛岋紝浣嗙粨鏋滃茍涓嶆槸鎸夌収欏哄簭鎺掑垪鐨勩傚鏋滀綘甯屾湜浠ュ瓧姣嶈〃欏哄簭灝嗙粨鏋滃垪鍑哄張璇ユ庝箞鍋氬憿錛熷彧瑕佷嬌鐢∣RDER BY瀛愬彞灝卞彲浠ユ寜鐓у崌搴忔垨闄嶅簭鏉ユ帓鍒楃粨鏋滐細
銆銆SELECT DISTINCT BRANCH_OFFICE
銆銆FROM EMPLOYEES
銆銆ORDER BY BRANCH_OFFICE ASC;
銆銆榪欎竴鏌ヨ鐨勭粨鏋滃琛?鎵紺恒傝娉ㄦ剰鍦∣RDER BY涔嬪悗鏄浣曟斁緗垪鍚岯RANCH _OFFICE鐨勶紝榪欏氨鏄垜浠兂瑕佸鍏惰繘琛屾帓搴忕殑鍒椼備負浠涔堝嵆浣挎槸緇撴灉琛ㄤ腑鍙湁涓涓垪鏃舵垜浠篃蹇呴』鎸囧嚭鍒楀悕鍛紵榪欐槸鍥犱負鎴戜滑榪樿兘澶熸寜鐓ц〃涓叾浠栧垪榪涜鎺掑簭錛屽嵆浣垮畠浠茍涓嶆樉紺哄嚭鏉ャ傚垪鍚岯RANCH_ OFFICE涔嬪悗鐨勫叧閿瓧ASC琛ㄧず鎸夌収鍗囧簭鎺掑垪銆傚鏋滀綘甯屾湜浠ラ檷搴忔帓鍒楋紝閭d箞鍙互鐢ㄥ叧閿瓧DESC銆?br />
銆銆鍚屾牱鎴戜滑搴旇鎸囧嚭ORDER BY瀛愬彞鍙皢涓存椂琛ㄤ腑鐨勭粨鏋滆繘琛屾帓搴忥紱騫朵笉褰卞搷鍘熸潵鐨勮〃銆?br />
銆銆鍋囪鎴戜滑甯屾湜寰楀埌鎸夐儴闂ㄦ帓搴忓茍浠庡伐璧勬渶楂樼殑闆囧憳鍒板伐璧勬渶浣庣殑闆囧憳鎺掑垪鐨勫垪琛ㄣ傞櫎浜嗗伐璧勬嫭鍙蜂腑鐨勫唴瀹癸紝鎴戜滑榪樺笇鏈涚湅鍒版寜鐓ц仒鐢ㄦ椂闂翠粠鏈榪戣仒鐢ㄧ殑闆囧憳寮濮嬪垪鍑虹殑鍒楄〃銆備互涓嬫槸浣犲皢瑕佺敤鍒扮殑璇彞錛?br />
銆銆SELECT BRANCH_OFFICE,FIRST_NAME,
銆銆 LAST_NAME,SALARY,HIRE_DATE
銆銆FROM EMPLOYEES
銆銆ORDER BY SALARY DESC,
銆銆 HIRE_DATE DESC;
銆銆榪欓噷鎴戜滑榪涜浜嗗鍒楃殑閫夋嫨鍜屾帓搴忋傛帓搴忕殑浼樺厛綰х敱璇彞涓殑鍒楀悕欏哄簭鎵鍐沖畾銆係QL灝嗗厛瀵瑰垪鍑虹殑絎竴涓垪榪涜鎺掑簭銆傚鏋滃湪絎竴涓垪涓嚭鐜頒簡閲嶅鐨勮鏃訛紝榪欎簺琛屽皢琚寜鐓х浜屽垪榪涜鎺掑簭錛屽鏋滃湪絎簩鍒椾腑鍙堝嚭鐜頒簡閲嶅鐨勮鏃訛紝榪欎簺琛屽張灝嗚鎸夌収絎笁鍒楄繘琛屾帓搴?#8230;…濡傛綾繪帹銆傝繖嬈℃煡璇㈢殑緇撴灉濡傝〃5鎵紺恒?br />
銆銆灝嗕竴涓緢闀跨殑琛ㄤ腑鐨勬墍鏈夊垪鍚嶅啓鍑烘潵鏄竴浠剁浉褰撻夯鐑︾殑浜嬶紝鎵浠QL鍏佽鍦ㄩ夋嫨琛ㄤ腑鎵鏈夌殑鍒楁椂浣跨敤*鍙鳳細
銆銆SELECT * FROM EMPLOYEES;
銆銆榪欐鏌ヨ榪斿洖鏁翠釜EMPLOYEES琛紝濡傝〃1鎵紺恒?br />
銆銆 涓嬮潰鎴戜滑瀵瑰紑濮嬫椂緇欏嚭鐨凷ELECT璇彞鐨勮娉曡繘琛屼竴涓嬫洿鏂幫紙绔栫洿綰胯〃紺轟竴涓彲閫夐」錛屽厑璁稿湪鍏朵腑閫夋嫨涓欏廣傦級錛?br />
銆銆SELECT [DISTINCT]
銆銆 (column [{, columns}])| *
銆銆FROM table [ {, table}]
銆銆[ORDER BY column [ASC] | DESC
銆銆 [ {, column [ASC] | DESC }]];
銆銆瀹氫箟閫夋嫨鏍囧噯
銆銆鍦ㄦ垜浠洰鍓嶆墍浠嬬粛鐨凷ELECT璇彞涓紝鎴戜滑瀵圭粨鏋滆〃涓殑鍒椾綔鍑轟簡閫夋嫨浣嗚繑鍥炵殑鏄〃涓墍鏈夌殑琛屻傝鎴戜滑鐪嬩竴涓嬪浣曞SELECT璇彞榪涜闄愬埗浣垮緱瀹冨彧榪斿洖甯屾湜寰楀埌鐨勮錛?br />
銆銆SELECT columns FROM tables [WHERE predicates];
銆銆WHERE瀛愬彞瀵規潯浠惰繘琛屼簡璁劇疆錛屽彧鏈夋弧瓚蟲潯浠剁殑琛屾墠琚寘鎷埌緇撴灉琛ㄤ腑銆傝繖浜涙潯浠剁敱鏂█錛坧redicate錛夎繘琛屾寚瀹氾紙鏂█鎸囧嚭浜嗗叧浜庢煇浠朵簨鎯呯殑涓縐嶅彲鑳界殑浜嬪疄錛夈傚鏋滆鏂█瀵逛簬鏌愪釜緇欏畾鐨勮鎴愮珛錛岃琛屽皢琚寘鎷埌緇撴灉琛ㄤ腑錛屽惁鍒欒琛岃蹇界暐銆傚湪SQL璇彞涓柇璦閫氬父閫氳繃姣旇緝鏉ヨ〃紺恒備緥濡傦紝鍋囧浣犻渶瑕佹煡璇㈡墍鏈夊涓篔ones鐨勮亴鍛橈紝鍒欏彲浠ヤ嬌鐢ㄤ互涓婼ELECT璇彞錛?br />
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE LAST_NAME = 'Jones';
銆銆LAST_NAME = 'Jones'閮ㄥ垎灝辨槸鏂█銆傚湪鎵ц璇ヨ鍙ユ椂錛孲QL灝嗘瘡涓琛岀殑LAST_NAME鍒椾笌“Jones”榪涜姣旇緝銆傚鏋滄煇涓鑱屽憳鐨勫涓?#8220;Jones”錛屽嵆鏂█鎴愮珛錛岃鑱屽憳鐨勪俊鎭皢琚寘鎷埌緇撴灉琛ㄤ腑錛堣琛?錛夈?br />
銆銆浣跨敤鏈澶氱殑鍏姣旇緝
銆銆鎴戜滑涓婁緥涓殑鏂█鍖呮嫭涓縐嶅熀浜?#8220;絳夊?#8221;鐨勬瘮杈冿紙LAST_NAME = 'Jones'錛夛紝浣嗘槸SQL鏂█榪樺彲浠ュ寘鍚叾浠栧嚑縐嶇被鍨嬬殑姣旇緝銆傚叾涓渶甯哥敤鐨勪負錛?br />
銆銆絳変簬 =
銆銆涓嶇瓑浜?<>
銆銆灝忎簬 <
銆銆澶т簬 >
銆銆灝忎簬鎴栫瓑浜?<=
銆銆澶т簬鎴栫瓑浜?>=
銆銆涓嬮潰緇欏嚭浜嗕笉鏄熀浜庣瓑鍊兼瘮杈冪殑涓涓緥瀛愶細
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE SALARY > 50000;
銆銆榪欎竴鏌ヨ灝嗚繑鍥炲勾钖珮浜?50,000.00鐨勮亴鍛橈紙鍙傝琛?錛夈?br />
銆銆閫昏緫榪炴帴絎?br />
銆銆鏈夋椂鎴戜滑闇瑕佸畾涔変竴鏉′笉姝竴縐嶆柇璦鐨凷ELECT璇彞銆備婦渚嬫潵璇達紝濡傛灉浣犱粎浠呮兂鏌ョ湅Davy Jones鐨勪俊鎭殑璇濓紝琛?涓殑緇撴灉灝嗘槸涓嶆紜殑銆備負浜嗚繘涓姝ュ畾涔変竴涓猈HERE瀛愬彞錛岀敤鎴峰彲浠ヤ嬌鐢ㄩ昏緫榪炴帴絎ND錛孫R鍜孨OT銆備負浜嗗彧寰楀埌鑱屽憳Davy Jones鐨勮褰曪紝鐢ㄦ埛鍙互杈撳叆濡備笅璇彞錛?br />
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE LAST_NAME = 'Jones' AND FIRST_NAME = 'Davy';
銆銆鍦ㄦ湰渚嬩腑錛屾垜浠氳繃閫昏緫榪炴帴絎ND灝嗕袱涓柇璦榪炴帴璧鋒潵銆傚彧鏈変袱涓柇璦閮芥弧瓚蟲椂鏁翠釜琛ㄨ揪寮忔墠浼氭弧瓚熾傚鏋滅敤鎴烽渶瑕佸畾涔変竴涓猄ELECT璇彞鏉ヤ嬌寰楀綋鍏朵腑浠諱綍涓欏規垚绔嬪氨婊¤凍鏉′歡鏃訛紝鍙互浣跨敤OR榪炴帴絎︼細
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE LAST_NAME = 'Jones' OR LAST_NAME = 'Smith';
銆銆鏈夋椂瀹氫箟涓涓柇璦鐨勬渶濂芥柟娉曟槸閫氳繃鐩稿弽鐨勬弿榪版潵璇存槑銆傚鏋滀綘鎯寵鏌ョ湅闄や簡Boston鍔炰簨澶勭殑鑱屽憳浠ュ鐨勫叾浠栨墍鏈夎亴鍛樼殑淇℃伅鏃訛紝浣犲彲浠ヨ繘琛屽涓嬬殑鏌ヨ錛?br />
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE NOT(BRANCH_OFFICE = 'Boston');
銆銆鍏抽敭瀛桸OT鍚庨潰璺熺潃鐢ㄥ渾鎷彿鎷搗鏉ョ殑姣旇緝琛ㄨ揪寮忋傚叾緇撴灉鏄緇撴灉鍙栧惁瀹氥傚鏋滄煇涓鑱屽憳鎵鍦ㄩ儴闂ㄧ殑鍔炰簨澶勫湪Boston錛屾嫭鍙峰唴鐨勮〃杈懼紡榪斿洖true錛屼絾鏄疦OT鎿嶄綔絎﹀皢璇ュ煎彇鍙嶏紝鎵浠ヨ琛屽皢涓嶈閫変腑銆?br />
銆銆鏂█鍙互涓庡叾浠栫殑鏂█宓屽浣跨敤銆備負浜嗕繚璇佸畠浠互姝g‘鐨勯『搴忚繘琛屾眰鍊鹼紝鍙互鐢ㄦ嫭鍙峰皢瀹冧滑鎷搗鏉ワ細
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE (LAST_NAME = 'Jones'
銆銆AND FIRST_NAME = 'Indiana')
銆銆OR (LAST_NAME = 'Smith'
銆銆AND FIRST_NAME = 'Bessie');
銆銆SQL娌跨敤鏁板涓婃爣鍑嗙殑琛ㄨ揪寮忔眰鍊肩殑綰﹀畾鈥斿渾鎷彿鍐呯殑琛ㄨ揪寮忓皢鏈鍏堣繘琛屾眰鍊鹼紝鍏朵粬琛ㄨ揪寮忓皢浠庡乏鍒板彸榪涜姹傚箋?br />
銆銆浠ヤ笂瀵歸昏緫榪炴帴絎﹁繘琛屼簡璇存槑錛屽湪瀵逛笅闈㈢殑鍐呭榪涜璇存槑涔嬪墠錛屾垜浠啀涓嬈″SELECT璇彞鐨勮娉曡繘琛屾洿鏂幫細
銆銆SELECT [DISTINCT]
銆銆 (column [{, column } ] )| *
銆銆FROM table [ { , table} ]
銆銆[ORDER BY column [ASC] | [DESC
銆銆[{ , column [ASC] | [DESC } ] ]
銆銆WHERE predicate [ { logical-connector predicate } ];
銆銆NULL鍜屼笁鍊奸昏緫
銆銆鍦⊿QL涓璑ULL鏄竴涓鏉傜殑璇濋錛屽叧浜嶯ULL鐨勮緇嗘弿榪版洿閫傚悎浜庡湪SQL鐨勯珮綰ф暀紼嬭屼笉鏄幇鍦ㄧ殑鍏ラ棬鏁欑▼涓繘琛屼粙緇嶃備絾鐢變簬NULL闇瑕佽繘琛岀壒孌婂鐞嗭紝騫朵笖浣犱篃寰堝彲鑳戒細閬囧埌瀹冿紝鎵浠ユ垜浠繕鏄畝鐣ュ湴榪涜涓涓嬭鏄庛?br />
銆銆棣栧厛錛屽湪鏂█涓繘琛孨ULL鍒ゆ柇鏃墮渶瑕佺壒孌婄殑璇硶銆備緥濡傦紝濡傛灉鐢ㄦ埛闇瑕佹樉紺烘墍鏈夊勾钖湭鐭ョ殑鑱屽憳鐨勫叏閮ㄤ俊鎭紝鐢ㄦ埛鍙互浣跨敤濡備笅SELECT璇彞錛?br />
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE SALARY IS NULL;
銆銆鐩稿弽錛屽鏋滅敤鎴烽渶瑕佹墍鏈夊凡鐭ュ勾钖暟鎹殑鑱屽憳鐨勪俊鎭紝浣犲彲浠ヤ嬌鐢ㄤ互涓嬭鍙ワ細
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE SALARY IS NOT NULL;
銆銆璇鋒敞鎰忔垜浠湪鍒楀悕涔嬪悗浣跨敤浜嗗叧閿瓧IS NULL鎴朓S NOT NULL錛岃屼笉鏄爣鍑嗙殑姣旇緝褰㈠紡錛欳OLUMN = NULL銆丆OLUMN <> NULL鎴栨槸閫昏緫鎿嶄綔絎OT錛圢ULL錛夈?br />
銆銆榪欑褰㈠紡鐩稿綋綆鍗曘備絾褰撲綘涓嶆槑紜湴嫻嬭瘯NULL錛堣屽畠浠‘瀹炲瓨鍦級鏃訛紝浜嬫儏浼氬彉寰楀緢娣蜂貢銆?br />
銆銆渚嬪錛屽洖榪囧ご鏉ョ湅鎴戜滑鍥?涓殑EM-PLOYEES琛紝鍙互鐪嬪埌Indiana Jones鐨勫伐钖瓑綰ф垨騫磋柂鍊奸兘鏄湭鐭ョ殑銆傝繖涓や釜鍒楅兘鍖呭惈NULL銆傚彲浠ユ兂璞¤繍琛屽涓嬬殑鏌ヨ錛?br />
銆銆SELECT * FROM EMPLOYEES
銆銆WHERE GRADE <= SALARY;
銆銆姝ゆ椂錛孖ndiana Jones搴旇鍑虹幇鍦ㄧ粨鏋滆〃涓傚洜涓篘ULL閮芥槸鐩哥瓑鐨勶紝鎵浠ュ彲浠ユ兂璞″畠浠槸鑳藉閫氳繃GRADE灝忎簬絳変簬SALARY鐨勬鏌ョ殑銆傝繖鍏跺疄鏄竴涓鏃犵枒涔夌殑鏌ヨ錛屼絾鏄茍娌℃湁鍏崇郴銆係QL鍏佽榪涜榪欐牱鐨勬瘮杈冿紝鍙涓や釜鍒楅兘鏄暟瀛楃被鍨嬬殑銆傜劧鑰岋紝Indiana Jones騫舵病鏈夊嚭鐜板湪鏌ヨ鐨勭粨鏋滀腑錛屼負浠涔堬紵
銆銆姝e鎴戜滑鏃╁厛鎻愬埌榪囩殑錛孨ULL琛ㄧず鏈煡鐨勫鹼紙鑰屼笉鏄薄鏌愪簺浜烘墍鎯寵薄鐨勯偅鏍瘋〃紺轟竴涓負NULL鐨勫鹼級銆傚浜嶴QL鏉ヨ鎰忓懗鐫榪欎釜鍊兼槸鏈煡鐨勶紝鑰屽彧瑕佽繖涓間負鏈煡錛屽氨涓嶈兘灝嗗叾涓庡叾浠栧兼瘮杈冿紙鍗充嬌鍏朵粬鍊間篃鏄疦ULL錛夈傛墍浠QL鍏佽闄や簡鍦╰rue 鍜宖alse涔嬪榪樻湁絎笁縐嶇被鍨嬬殑鐪熷鹼紝縐頒箣涓?#8220;闈炵‘瀹?#8221;錛坲nknown錛夊箋?br />
銆銆濡傛灉姣旇緝鐨勪袱杈歸兘鏄疦ULL錛屾暣涓柇璦灝辮璁や負鏄潪紜畾鐨勩傚皢涓涓潪紜畾鏂█鍙栧弽鎴栦嬌鐢ˋND鎴朞R涓庡叾浠栨柇璦榪涜鍚堝茍涔嬪悗錛屽叾緇撴灉浠嶆槸闈炵‘瀹氱殑銆傜敱浜庣粨鏋滆〃涓彧鍖呮嫭鏂█鍊間負“鐪?#8221;鐨勮錛屾墍浠ULL涓嶅彲鑳芥弧瓚寵媯鏌ャ備粠鑰岄渶瑕佷嬌鐢ㄧ壒孌婄殑鎿嶄綔絎S NULL鍜孖S NOT NULL銆?br />
銆銆UPDATE璇彞
銆銆UPDATE璇彞鍏佽鐢ㄦ埛鍦ㄥ凡鐭ョ殑琛ㄤ腑瀵圭幇鏈夌殑琛岃繘琛屼慨鏀廣?br />
銆銆渚嬪錛屾垜浠垰鍒氬彂鐜癐ndiana Jones鐨勭瓑綰т負16錛屽伐璧勪負$40,000.00錛屾垜浠彲浠ラ氳繃涓嬮潰鐨凷QL璇彞瀵規暟鎹簱榪涜鏇存柊錛堝茍娓呴櫎閭d簺鐑︿漢鐨凬ULL錛夈?br />
銆銆UPDATE EMPLOYEES
銆銆SET GRADE = 16, SALARY = 40000
銆銆WHERE FIRST_NAME = 'Indiana'
銆銆 AND LAST_NAME = 'Jones';
銆銆涓婇潰鐨勪緥瀛愯鏄庝簡涓涓崟琛屾洿鏂幫紝浣嗘槸UPDATE璇彞鍙互瀵瑰琛岃繘琛屾搷浣溿傛弧瓚砏HERE鏉′歡鐨勬墍鏈夎閮藉皢琚洿鏂般傚鏋滐紝浣犳兂璁〣oston鍔炰簨澶勪腑鐨勬墍鏈夎亴鍛樻惉鍒癗ew York錛屼綘鍙互浣跨敤濡備笅璇彞錛?br />
銆銆UPDATE EMPLOYEES
銆銆SET BRANCH_OFFICE = 'New York'
銆銆WHERE BRANCH_OFFICE = 'Boston';
銆銆濡傛灉蹇界暐WHERE瀛愬彞,琛ㄤ腑鎵鏈夎涓殑閮ㄩ棬鍊奸兘灝嗚鏇存柊涓?New York'銆?br />
銆銆UPDATE璇彞鐨勮娉曟祦鍥懼涓嬮潰鎵紺猴細
銆銆UPDATE table
銆銆SET column = value [{, column = value}]
銆銆[ WHERE predicate [ { logical-connector predicate}]];
銆銆DELETE璇彞
銆銆DELETE璇彞鐢ㄦ潵鍒犻櫎宸茬煡琛ㄤ腑鐨勮銆傚鍚孶PDATE璇彞涓竴鏍鳳紝鎵鏈夋弧瓚砏HERE瀛愬彞涓潯浠剁殑琛岄兘灝嗚鍒犻櫎銆傜敱浜嶴QL涓病鏈塙NDO璇彞鎴栨槸“浣犵‘璁ゅ垹闄ゅ悧錛?#8221;涔嬬被鐨勮鍛婏紝鍦ㄦ墽琛岃繖鏉¤鍙ユ椂鍗冧竾瑕佸皬蹇冦傚鏋滃喅瀹氬彇娑圠os Angeles鍔炰簨澶勫茍瑙i泧鍔炰簨澶勭殑鎵鏈夎亴鍛橈紝榪欎竴鍗戦剻鐨勫伐浣滃彲浠ョ敱浠ヤ笅榪欐潯璇彞鏉ュ疄鐜幫細
銆銆DELETE FROM EMPLOYEES
銆銆WHERE BRANCH_OFFICE = 'Los Angeles';
銆銆濡傚悓UPDATE璇彞涓竴鏍鳳紝鐪佺暐WHERE瀛愬彞灝嗕嬌寰楁搷浣滄柦鍔犲埌琛ㄤ腑鎵鏈夌殑琛屻?br />
銆銆DELETE璇彞鐨勮娉曟祦鍥懼涓嬮潰鎵紺猴細
銆銆DELETE FROM table
銆銆[WHERE predicate [ { logical-connector predicate} ] ];
銆銆鐜板湪鎴戜滑瀹屾垚浜嗘暟鎹搷浣滆璦錛圖ML錛夌殑涓昏璇彞鐨勪粙緇嶃傛垜浠茍娌℃湁瀵筍QL鑳藉畬鎴愮殑鎵鏈夊姛鑳借繘琛岃鏄庛係QL榪樻彁渚涗簡璁稿鐨勫姛鑳斤紝濡傛眰騫沖潎鍊箋佹眰鍜屼互鍙婂叾浠栧琛ㄤ腑鏁版嵁鐨勮綆楋紝姝ゅSQL榪樿兘瀹屾垚浠庡涓〃涓繘琛屾煡璇紙澶氳〃鏌ヨ錛屾垨縐頒箣涓鴻繛鎺ワ級鐨勫伐浣溿傝繖縐嶈璦榪樺厑璁鎬綘浣跨敤GRANT鍜孯EVOKE鍛戒護鎺у埗浣跨敤鑰呯殑鏁版嵁璁塊棶鏉冮檺銆?/span>

]]>
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