asp.net,c#,sql server

摘要: sometimes all it takes is a little tweak here or there to make your application run much faster. Ah, but the key is figuring out how to tweak it! Sooner or later you'll face a situation where a SQL qu...阅读全文

摘要: 可以使用 PIVOT 和 UNPIVOT 关系运算符将表值表达式更改为另一个表。PIVOT 通过将表达式某一列中的唯一值转换为输出中的多个列来旋转表值表达式，并在必要时对最终输出中所需的任何其余列值执行聚合。UNPIVOT 与 PIVOT 执行相反的操作，将表值表达式的列转换为列值。注意：对升级到 Microsoft SQL Server 2005 的数据库使用 PIVOT 和 UNPIVOT 时...阅读全文

摘要: The beauty of returning a pointer to an object, is that you can return NULL as your standard error return value, and if the value mattered, you will most likely take the necessary steps to check its r...阅读全文