EntityModel的定义是: Personnel有一个国家/地区的链接
当在LinqPad中执行这段代码时,我看到在第一个查询中生成的SQL没有优化(所有字段都被返回)?我在这里遗漏了什么或者做错了什么?
查询1 LINQ
var Country = Countries.FirstOrDefault(o => o.Id == 100000581);
var personnelIds = Country.Personnels.Select(p => p.Id).ToArray();
personnelIds.Dump();
查询%1 SQL
exec sp_executesql N'SELECT [t0].[Id], [t0].[Version], [t0].[Identifier], [t0].[Name], , [t0].[UpdatedBy] FROM [Personnel] AS [t0] WHERE [t0].[Country_Id] = @p0',N'@p0 bigint',@p0=100000581
查询2 LINQ
var Country = Countries.FirstOrDefault(o => o.Id == 100000581);
var personnelIds2 = Personnels.Where(p => p.Country == Country).Select(p => p.Id).ToArray();
personnelIds2.Dump();
查询2 SQL
exec sp_executesql N'SELECT [t0].[Id] FROM [Personnel] AS [t0] WHERE [t0].[Country_Id] = @p0',N'@p0 bigint',@p0=100000581
使用的数据库是SQL Express 2008。LinqPad版本为4.43.06
https://stackoverflow.com/questions/15690756
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