濡備綍瑙ｅ喅Hibernate 鐨凬+1闂
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聽 聽聽 聽聽 聽2錛夊瀵逛竴<many-to-one>聽聽錛屽湪澶氱殑杩欐柟錛岄?杩?鏉ql鏌ヨ寰楀埌浜唍涓璞★紝鐢變簬鍏寵仈鐨勫瓨鍦?涔熶細灝嗚繖n涓璞″搴旂殑1 鏂圭殑瀵硅薄鍙栧嚭錛?浜庢槸鏈潵鐨?鏉ql鏌ヨ鍙樻垚浜? +n鏉?銆?/span>
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聽 聽聽 聽聽 聽3錛塱terator 鏌ヨ鏃?涓?畾鍏堝幓緙撳瓨涓壘錛?鏉ql鏌ラ泦鍚?鍙煡鍑篒D錛夛紝鍦ㄦ病鍛戒腑鏃訛紝浼氬啀鎸塈D鍒闆簱涓?涓?煡鎵撅紝 浜х敓1+n鏉QL銆?/span>
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銆?/span>瑙ｅ喅鍔炴硶銆?/span>
聽 聽聽聽聽 聽聽聽1錛塴azy=true錛?hibernate3寮?宸茬粡榛樿鏄痩azy=true浜嗭紱lazy=true鏃朵笉浼氱珛鍒繪煡璇㈠叧鑱斿璞★紝鍙湁褰撻渶瑕佸叧鑱斿璞★紙璁塊棶鍏跺睘鎬э紝闈瀒d瀛楁錛夋椂鎵嶄細鍙戠敓鏌ヨ鍔ㄤ綔銆?/span>
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聽 聽聽 聽聽 聽 2錛変嶠鐢ㄤ簩綰х紦瀛橈紝 浜岀駭緙撳瓨鐨勫簲鐢ㄥ皢涓嶆?1+N 闂錛屽洜涓哄嵆浣跨涓?鏌ヨ寰堟參錛堟湭鍛戒腑錛夛紝浠ュ悗鏌ヨ鐩存帴緙撳瓨鍛戒腑涔熸槸寰堝揩鐨勩?鍒氬ソ鍙堝埄鐢ㄤ簡1+N 銆?/span>
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聽 聽聽 聽聽 聽 3 ) 褰撶劧浣犱篃鍙互璁懼畾fetch="join"錛屼竴嬈″叧鑱旇〃鍏ㄦ煡鍑烘潵錛屼絾澶卞幓浜嗗歡杩熷姞杞界殑鐗規?銆?/span>
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