将SQL语句转换为Linq-2-Sql

Question

如何将下列SQL语句转换为L2S？

SELECT DefaultCode, MAX(EffectiveDt) AS EffectiveDt 
FROM tblDF_DefaultSetting 
GROUP BY DefaultCode 

Answer 1

您想使用DefaultCode的GroupBy操作和使用Select操作员与两个值创建一个新的匿名类你感兴趣的内容。

dataContext.tblDF_DefaultSetting 
    .GroupBy(x => x.DefaultCode) 
    .Select(x => new { DefaultCode = x.Key, EffectiveDt = x.Max(x => x.EffectiveDt) });