數據庫
數據庫相關:Oracle,Sql Server,MySql,DB2,informix,sql語句......
摘要: As per the documentation on MySQL I moved the storage of passwords from using Password() to using MD5(). I read a number of places that stated that this was a method that couldn't be reversed and it was far more secure than the previous method. I was feeling confident that life was about to get a little more secure. While going through my daily RSS feeds and mailing lists for SpikeSource, I happenned upon a thread about someone discussing how easy it was to break MD5 hashes. It was a simple matt
閱讀全文
摘要: 1.如果存在就更新，不存在就插入用一個語句實;
2.分頁算法;
3.抽取/刪除重復記錄;
閱讀全文
摘要: Hibernate中支持3種形式實現繼承關系：
1. Table per concrete class 表與子類之間獨立一對一關系
2. Table per subclass 每個子類對應一張子表，并與主類共享主表
3. Table per class hierarchy 表與類一對多關系
閱讀全文
Full 數據庫 Archive