将SQL语句转换为Linq-2-Sql

Question

如何将以下SQL语句转换为L2S？

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

Answer 1

您想在DefaultCode上使用GroupBy运算符，并使用Select运算符使用您感兴趣的两个值创建一个新的匿名类型。

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