sql查询
摘要:student kemuA语文A 语文A 数学B语文B 数学如何实现查询:student 语文 数学A 2 1B 11SQL:select student ,sum(case kemu when '语文' then 1 esle 0 end) 语文, sum(case kemu when '数学then 1 esle 0 end) 数学from table group by student
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2013-01-10 11:38
HonestPeople
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数据库优化工具及如何进行优化
摘要:http://www.cnblogs.com/chillsrc/archive/2009/09/21/1571444.html 下一篇:http://www.cnblogs.com/chillsrc/archive/2009/09/23/1572743.html
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2013-01-06 11:46
HonestPeople
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