2008年1月10日

SQL Server SQL语句调优技巧

摘要: 子查询优化 一条好的值得称赞的规则是尽量用连接代替所有的子查询。优化器有时可以自动将子查询“扁平化”,并且用常规或外连接代替。但那样也不总是有效。明确的连接对选择表的顺序和找到最可能的计划给出了更多的选项。当你优化一个特殊查询时,了解一下是否去掉自查询可产生很大的差异。 示例 下面查询选择了pubs数据库中所有表的名字,以及每个表的聚集索引(如果存在)。如果没有聚集索引,表... 阅读全文

posted @ 2008-01-10 09:54 Wind Snail 阅读(516) 评论(1) 推荐(0) 编辑

Increase IIS/WinXP connection limit (or how to avoid HTTP 403.9 error)

摘要: 40 simultaneous connections!! Couple that with no HTTP Keep-Alives and it may actually work for you... From that post (for my own reference, as it was down some days ago):A lot of people were pinging ... 阅读全文

posted @ 2008-01-10 09:33 Wind Snail 阅读(536) 评论(0) 推荐(0) 编辑

Ten Common Database Design Mistakes

摘要: So, the list: Poor design/planning Ignoring normalization Poor naming standards Lack of documentation One table to hold all domain values Using identity/guid columns as your o... 阅读全文

posted @ 2008-01-10 09:30 Wind Snail 阅读(326) 评论(0) 推荐(0) 编辑

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