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摘要： The virtual keyword is used to modify a method, property, indexer or event declaration, and allow it to be overridden in a derived class. For example, this method can be overridden by any class that i... 阅读全文

摘要： select * from table1inner join table2inner join table3 on table2.id=table3.id on table1.id=table3.idwhere ...order by 阅读全文