内部异常错误：INSERT 语句与 FOREIGN KEY 约束冲突

Question

我正在尝试将 Ticket Table 的 Id 添加到另一个表 (TrackTicket) 并将其插入到字段 (TicketId) 中，但出现此错误

错误：EntityFramework.dll 中出现“System.Data.Entity.Infrastructure.DbUpdateException”类型的异常，但未在用户代码中处理

-- 内部异常错误：插入语句与外键约束冲突\“FK_dbo.TrackTickets_dbo.Tickets_TicketId\”。冲突发生在数据库\"databasename"\", table\"dbo.Tickets"\, column 'Id'.\语句已终止

这是什么意思？救命！

代码

控制器

_context.Tickets.Add(new Ticket {ClientId = userId , Subject = viewModel.Ticket.Subject, TypeOfTicket = viewModel.Ticket.TypeOfTicket, ConcernedDept = viewModel.Ticket.ConcernedDept, Date = DateTime.Now});

_context.TicketContents.Add(new TicketContent {Subject = viewModel.Ticket.Subject, Content = viewModel.TicketContent.Content});

_context.TrackTickets.Add(new TrackTicket { ClientId = userId,TicketId = viewModel.Ticket.Id  ,StatusHelpDesk = "Received", DateHelpDeskReceived = DateTime.Now });

_context.SaveChanges();

Answer 1

我不完全了解您的计划，但您正在创建或插入新票证，并且在您没有设置或检索票证的 id 时创建或插入引用票证的轨道票证。

此行还没有 id。要么在此处设置 id，要么创建变量票证并使用该 id 链接到 TrackTickets。 _context.Tickets.Add(new Ticket {ClientId = userId, Subject = viewModel.Ticket.Subject, TypeOfTicket = viewModel.Ticket.TypeOfTicket, ConcernedDept = viewModel.Ticket.ConcernedDept, Date = DateTime.Now});

添加将失败，因为 TicketId 无法链接到某些东西（没有插入具有该 ID 的票证。

_context.TrackTickets.Add(new TrackTicket { ClientId = userId, TicketId = viewModel.Ticket.Id, StatusHelpDesk = "Received", DateHelpDeskReceived = DateTime.Now });

如果您自动生成ticketId，您可以使用它的方式如下：

var newTicket = new Ticket {ClientId = userId, Subject = viewModel.Ticket.Subject, TypeOfTicket = viewModel.Ticket.TypeOfTicket, ConcernedDept = viewModel.Ticket.ConcernedDept, Date = DateTime.Now}  
_context.Tickets.Add(newTicket);
_context.SaveChanges();

如果您现在重用 newTicket 对象，这将有一个 id。所以在添加trackTickets时，使用newTicket的id

_context.TrackTickets.Add(new TrackTicket { ClientId = userId, TicketId = newTicket.Id, StatusHelpDesk = "Received", DateHelpDeskReceived = DateTime.Now });

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如果您不自动生成票证 ID，则必须在创建票证时设置 ID（添加到上下文）：

var newTicket = new Ticket { Id = viewModel.Ticket.Id, ClientId = userId, Subject = viewModel.Ticket.Subject, TypeOfTicket = viewModel.Ticket.TypeOfTicket, ConcernedDept = viewModel.Ticket.ConcernedDept, Date = DateTime.Now}