1銆備粈涔堟槸瀛愭煡璇紵
灝嗕竴涓煡璇㈠寘鍚埌鍙︿竴涓煡璇腑銆?BR>2銆傚伐浣滃師鐞嗭紵
瀛愭煡璇㈡槸鐗靛鍦ㄥ彟涓涓猻elect璇彞涓殑select璇彞銆傚唴閮╯elect璇彞榪斿洖鐢ㄤ綔浜庡閮╯elect璇彞鐨勬潯浠剁殑鍒椼傞鍏堜粠鏈鍐呴儴鐨剆elect寮濮嬫墽琛屻?BR>
3銆傚湪澶у鏁版煡璇腑錛屽瓙鏌ヨ騫朵笉寮曠敤鐖舵煡璇€傚洜姝ゅ瓙鏌ヨ涓殑鍊間繚鎸佷笉鍙樸備緥濡傦細
//MSSQL
//閫氳繃IN OR NOT IN寮曞叆鐨勫瓙鏌ヨ緇撴灉
//鏄竴鍒楅浂鍊兼垨鏇村鍊?BR>//鎶婏紙titles錛夊瓙鏌ヨ閲岀粨鏋滀綔涓?BR>//(publicshers)鐖舵煡璇㈢殑鏉′歡榪涜鏌ヨ
USE PUBS
SELECT PUB_NAME TITLE
FROM PUBLICSHERS
WHERE PUB_ID IN(
SELECT PUB_ID FROM TITLES
WHERE TYPE = 'BUSSINESS')
//閫氳繃IN OR NOT IN寮曞叆鐨勫瓙鏌ヨ緇撴灉
//鏄竴鍒楅浂鍊兼垨鏇村鍊?BR>//鎶婏紙titles錛夊瓙鏌ヨ閲岀粨鏋滀綔涓?BR>//(publicshers)鐖舵煡璇㈢殑鏉′歡榪涜鏌ヨ
USE PUBS
SELECT PUB_NAME TITLE
FROM PUBLICSHERS
WHERE PUB_ID IN(
SELECT PUB_ID FROM TITLES
WHERE TYPE = 'BUSSINESS')
濡傛灉瀛愭煡璇㈠紩鐢ㄤ簡鐖舵煡璇紝灝遍渶瑕佷負鐖舵煡璇腑鐨勬瘡嬈¤凱浠ｉ噸鏂拌綆楀瓙鏌ヨ鐨勫箋?BR>
//瀛愭煡璇腑鐢ㄥ埌浜嗙埗鏌ヨ鐨勫?BR>//鍦ㄦ湁澶ч噺鏁版嵁鐨勬椂鍊欏敖閲忛伩鍏嶄嬌鐢ㄦ綾繪煡璇?BR>//瀹冩煡璇㈡暟鎹彲鏄垚鎸囨暟澧為暱鐨?BR>USE PUBS
SELECT A.CITY FROM SUPPLIERS A
WHERE A.SUPPLIERID IN (
SELECT B.SUPPLIERID FROM PRODUCTS B
WHERE A.SUPPLIERID = B.SUPPLIERID)
SELECT A.CITY FROM SUPPLIERS A
WHERE A.SUPPLIERID IN (
SELECT B.SUPPLIERID FROM PRODUCTS B
WHERE A.SUPPLIERID = B.SUPPLIERID)
4銆傛垜瑕佽涓涓嬭仈鎺ュ拰瀛愭煡璇㈢殑鍖哄埆
鑱旀帴涓庡瓙鏌ヨ澶勭悊綾諱技闂涓嶅悓涔嬪鍦ㄤ簬錛岃仈鎺ュ彲浠ュ湪緇撴灉闆嗕腑鏄劇ず澶氫釜琛ㄧ殑鍒椼?BR> 鍙寵仈鎺ュ氨鏄煡璇㈠寘鍚簡鍙寵竟琛ㄧ殑鍏ㄩ儴璁板綍錛屽嵆浣垮乏杈硅〃涓病鏈夊尮閰嶇殑鍊箋?BR> 宸﹁仈鍜屽彸鑱旀濂界浉鍙?BR>
//鍐呰仈鎺?BR>USE PUBS
SELECT A.PUB_NAME, A.TITLE
FROM PUBLISHERS A INNER JOIN TITLES B
ON A.PUB_ID = B.PUB_ID
AND TYPE = 'BUSSINESS')
SELECT A.PUB_NAME, A.TITLE
FROM PUBLISHERS A INNER JOIN TITLES B
ON A.PUB_ID = B.PUB_ID
AND TYPE = 'BUSSINESS')
5銆傚叧浜庝嬌鐢‥XISTS AND NOT EXISTS鐨勫瓙鏌ヨ
浣跨敤EXISTS寮曞叆涓涓瓙鏌ヨ錛屽氨鐩稿綋浜庤繘琛屼竴嬈″瓨鍦ㄧ殑嫻嬭瘯錛屽閮ㄦ煡璇㈢殑WHERE瀛愬彞嫻嬭瘯瀛愭煡璇?BR>榪斿洖鐨勮鏄惁瀛樺湪銆傚瓙鏌ヨ涓嶄駭鐢熶換浣曠粨鏋滐紱瀹冨彧榪斿洖TRUE鎴朏ALSE鍊箋?BR>
//鏌ユ壘瀛樺湪鍟嗕笟涔︾睄鐨勫嚭鐗堝晢鐨勫悕瀛?BR>//鍜屽唴鑱斿姣斾笅鏈変粈涔堜笉鍚?BR>USE PUBS
SELECT A.PUB_NAME
FROM PUBLISHERS A
WHERE EXISTS (
SELECT *FROM TITLES
WHERE PUB_ID = A.PUB_ID
AND TYPE = 'BUSSINESS')
//瀛愭煡璇?鍐嶆瀵規瘮涓?BR>USE PUBS
SELECT PUB_NAME
FROM PUBLISHERS
WHERE PUB_ID IN (
SELECT PUB_ID FROM TITLES
WHERE TYPE = 'BUSSINESS')
SELECT A.PUB_NAME
FROM PUBLISHERS A
WHERE EXISTS (
SELECT *FROM TITLES
WHERE PUB_ID = A.PUB_ID
AND TYPE = 'BUSSINESS')
//瀛愭煡璇?鍐嶆瀵規瘮涓?BR>USE PUBS
SELECT PUB_NAME
FROM PUBLISHERS
WHERE PUB_ID IN (
SELECT PUB_ID FROM TITLES
WHERE TYPE = 'BUSSINESS')
閫氳繃嫻嬭瘯鎴戠寽鎯矱XISTS鍏抽敭瀛楀畠鐨勫伐浣滃師鐞嗘槸錛氶亶鍘嗘墍鏈夌殑璁板綍錛屾瘡閬嶅巻涓鏉¤褰曪紝瀛愭煡璇㈠氨鍒ゆ柇鏄惁瀛樺湪錛屽瓨鍦ㄧ殑璇濇弧瓚蟲潯浠舵樉紺鴻繖鏉¤褰曪紝鐒跺悗涓鐩存壘鍒版渶鍚庢潯璁板綍銆傦紙濡傛灉鏈変笉瀵圭殑鍦版柟鎴栬呴渶瑕佹敼榪涚殑鍦版柟錛岃澶у瑕佸憡璇夋垜鍟婏級
浠婂ぉ灝卞埌榪欓噷鎶婏紝璞℃垜榪欎箞鐗涚殑韜綋涔熺粡涓嶈搗緇忓父鐔+_+!銆?BR>
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