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比如我們現在有一個Parent的實體,在Parent實體當中有一個children的Set由於這個children的資料並非非常重要,為了方便,我們在修改parent的時候,做法經常都是1,清空children全部刪了,再把新的children全部加進去。今天早上做這一方面工作的時候遇到一個問題,就是在更新parent的時候,報了一個Don't dereference a collection with cascade="all-delete-orphan"的異常,經常一半個小時的查資料和調試,

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題目: A hard puzzleCrawling in process...Crawling failedTime Limit:1000MS    Memory Limit:32768KB   64bit IO Format:%I64d & %I64uSubmitStatusPracticeHDU 1097Descriptionlcy gives a hard puzzle to feng5166,lwg,JGShining and Ignatius:  gave a and

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題目:ExponentiationTime Limit: 500MS Memory Limit: 10000KTotal Submissions: 100905 Accepted: 24250DescriptionProblems involving the computation of exact values of very large magnitude and precision are common. For example, the computation of the

poj 1007 –DNA Sorting解題報告

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log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).log4j:WARN Please initialize the log4j system properly.org.hibernate.MappingException: Unsupported cascade style: save_update    at

The security settings could not be applied to the database because the connection has failed with th

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【url】The reference to entity “characterEncoding” must end with the ‘;’ delim

資料來源配置時加上編碼轉換格式後出問題了:The reference to entity "characterEncoding" must end with the ';' delimiter這個錯誤就是 context.xml中設定資料來源連結URL的問題    <context-param>    <param-name>url</param-name>   

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stl 在ACM中的應用

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pku 1152 An Easy Problem!

 第一次寫解題報告 呵呵 !I -An Easy Problem!Crawling in process...Crawling failedTime Limit:1000MS   Memory Limit:10000KB   64bit IO Format:%I64d & %I64u                                                                                                        

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