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  • C# linq group by 异常 -----MySqlException: Unknown column 'GroupBy1.K1' in 'field list'

    使用Linq group by 查询 一般我们都会这样写Linq:

    var result = (from si in model.table group si by si.NumCores into grp orderby grp.Key select new CoreCount { Cores = grp.Key, Count = grp.Count() }).ToList(); 正确的答案(MySql):
    var result = (from si in model.table group si by si.NumCores into grp orderby grp.Key select new CoreCount { Cores = grp.FirstOrDefault().NumCores, Count = grp.Count() }).ToList();


    以上在MySQL亲测有效,SQL server没有测试。。。
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  • 原文地址:https://www.cnblogs.com/pzxnet/p/13171194.html
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