Linq to sql导致外键约束错误

Question

这是重要的代码.

       TournamentTeam newTeam = new TournamentTeam();
        TournamentTeams.InsertOnSubmit(newTeam);
        SubmitChanges();

        TournamentParticipant newSignup = new TournamentParticipant
        {
            CheckedIn = false,
            TournamentID = tournamentId,
            UserID = participant.UserID,
            TeamID = newTeam.TeamId
        };

        TournamentParticipants.InsertOnSubmit(newSignup);
        SubmitChanges();

TournamentParticipants.TeamId在TournamentTeam.TeamID上有一个fk关系,TeamID是一个标识列

我不明白的是,当TournamentTeam获得插入时,它会获取新的身份值.即使我调试代码,新的注册也会收到新的团队ID.但是当涉及到生成插入时,它完全避免了这个值,并在select语句之前插入,它抓取了新的标识列.

exec sp_executesql N'INSERT INTO [dbo].[TournamentParticipants]([UserID], [TournamentID], [CheckedIn]) VALUES (@p0, @p1, @p2)

SELECT [t0].[TeamID] FROM [dbo].[TournamentParticipants] AS [t0] WHERE ([t0].[UserID] = @p3) AND ([t0].[TournamentID] = @p4)',N'@p0 int,@p1 int,@p2 bit,@p3 int,@p4 int',@p0=29805,@p1=247,@p2=0,@p3=29805,@p4=247

如何让linq to sql使用我指定的团队id的值,或者在insert语句之前生成select语句？

Answer 1

而不是设置TeamID,将Team实体设置为您刚刚创建的实体.延迟SubmitChanges插入两者,然后它将在插入完成后修复id.

TournamentTeam newTeam = new TournamentTeam();
TournamentTeams.InsertOnSubmit(newTeam);

TournamentParticipant newSignup = new TournamentParticipant
{
    CheckedIn = false,
    TournamentID = tournamentId,
    UserID = participant.UserID,
    Team = newTeam
};

TournamentParticipants.InsertOnSubmit(newSignup);
SubmitChanges();