The way you'd do a join on more than one criteria generally is to use an anonymous type: join pc in productcategory on new { Id = p.Id, Other = ... ... <看更多>

from project in _db.Projects. join typeOfficial in _db.GuidContents on (short?)project.TypeOfficial equals typeOfficial.Value into TtypeOfficial. ... <看更多>

LINQ To DB supports all standard SQL join types: INNER, LEFT, FULL, RIGHT, CROSS JOIN. For join types that do not have ... Join operator on multiple columns. ... <看更多>