连接linq上的重复值

Question

我对结果有一些问题，我在连接上得到重复而不是两个具有不同值的重复项。 db包含这两个值，但其中一个在文本字段中有不同的值，为什么我得到重复，唯一相同的是CompanyPageId）。

 var query = (from pageEducation in _context.PageEducations
            join companyPage in _context.Pages on pageEducation.CompanyPageId equals companyPage.Id into p
            from companyPage in p.DefaultIfEmpty()
            where pageEducation.PageId == pageId
            select new PageEducation
            {
                Id = pageEducation.Id,
                PageId = pageEducation.PageId,
                CompanyPageId = pageEducation.CompanyPageId,
                CustomCompany = pageEducation.CustomCompany,
                CompanyPage = companyPage != null ? new Page {Name = companyPage.Name, Id = companyPage.Id} : null,
                Education = pageEducation.Education
            }).ToList();

我的表格如下：

CompanyPageId, education
33             edu1
33             edu2

，结果是包含两个项目的列表，但重复。

当我在SQL中运行此查询时，我不会得到任何重复项：

select * from Page_Educations
left join Pages on page_Educations.CompanyPageId = pages.Id                
where page_Educations.PageId = 10

当我在LinqPad中运行linq时，它甚至可以正常工作

 var query = from pageEducation in Page_Educations
            join companyPage in Pages on pageEducation.CompanyPageId equals companyPage.ID into p
            from companyPage in p.DefaultIfEmpty()
            where pageEducation.PageId == 10
            select new 
            {
                Id = pageEducation.Id,
                PageId = pageEducation.PageId,
                CompanyPageId = pageEducation.CompanyPageId,
                CustomCompany = pageEducation.CustomCompany,
                CompanyPage = companyPage != null ? new {Name = companyPage.Name, Id = companyPage.ID} : null,
                Education = pageEducation.Education
            };

       query.Dump();