c# - 如何将 SQL 查询转换为 LINQ to Entities 查询？

Question

SQL查询：

SELECT   

'ETS' AS dataSource, 
ES.ShowId, 
ES.Title, 
EE.EpisodeId, 
EE.Title AS EpisodeTitle, 
ELG.GenreDescription 
AS Genre, 
ELST.ShowTypeDescription, 
dbo.TVData_UDF_ETS_DirectorString(ES.ShowId) AS DirectorName, 
ES.ReleaseYear, 
EE.SeasonEpisode

FROM dbo.ETS_Shows AS ES 
LEFT OUTER JOIN dbo.ETS_Episodes AS EE 
ON ES.ShowId = EE.ShowId 

LEFT OUTER JOIN dbo.ETS_LKP_Genres AS ELG 
ON ES.GenreCode = ELG.GenreCode 

LEFT OUTER JOIN dbo.ETS_LKP_ShowTypes AS ELST 
ON ES.ShowTypeCode = ELST.ShowTypeCode

我正在尝试这样做，但它没有返回正确的数据：

var data = db.ETS_Shows.Include("ETS_Episodes").Include("ETS_LKP_Genres").Include("ETS_LKP_ShowTypes").ToList();

谁能帮我一把？

Answer 1

我想到了：

var query = from shows in db.ETS_Shows
                        from episodes in db.ETS_Episodes.Where(v => v.ShowId == shows.ShowId).DefaultIfEmpty()
                        from genres in db.ETS_LKP_Genres.Where(s => s.GenreCode == shows.GenreCode).DefaultIfEmpty()
                        from showTypes in db.ETS_LKP_ShowTypes.Where(z => z.ShowTypeCode == shows.ShowTypeCode).DefaultIfEmpty()
                        from directors in db.ETS_Directors.Where(p => p.ShowId == shows.ShowId).DefaultIfEmpty()
                        select new 
                            {
                                dataSource = "ETS",
                                shows.Title,
                                episodes.EpisodeId,
                                episodes.EpisodeTitle,
                                genres.GenreDescription,
                                showTypes.ShowTypeDescription,
                                directors.Name,
                                shows.ReleaseYear,
                                episodes.SeasonEpisode,
                                shows.ShowId
                            };