Myujth

Exception Argument types do not match is thrown, although both of them are DateTime.
Exception is thrown at

CreatedAt = db.TransactionLogs
 .Last(x => x.TransactionId == a.Id) 
 .CreatedAt

Query works just fine if I put CreatedAt = DateTime.Now() instead

TransactionLogs.CreatedAt is not nullable and I don't understand what's the issue.

public IList<HeadlineDisplayModel> GetTeamApplicationHeadlines(string userId, int year)
 
 using (var db = new TrainingManagerDbContext(Options))
 
 return (from a in db.Transactions
 join o in db.Options on a.OptionId equals o.Id
 join e in db.Employees on a.EmployeeId equals e.Id
 join s in db.TransactionStatuses on a.TransactionStatusId equals s.Id
 where
 a.Employee.DirectManagerId == userId
 && a.TransactionStatus.Id != TransactionStatus.DRAFT
 && !a.IsDeleted
 && a.BudgetYear == year
 select new HeadlineDisplayModel
 
 Title = o.Title,
 TransactionId = a.Id,
 DateFrom = a.PeriodFrom,
 Price = a.Price,
 StatusName = s.Name,
 EmployeeFullName = e.FullName,
 CreatedAt = db.TransactionLogs.Last(x => x.TransactionId == a.Id)
 .CreatedAt
 ).OrderByDescending(x => x.CreatedAt).ToList();
 
 

HeadlineDisplayModel

public DateTime CreatedAt get; set;


TransactionLog

[Required]
[Column("created_at", TypeName = "datetime")]
public DateTime CreatedAt get; set; 

 USE [KanbanBoard]
GO

/****** Object: Table [tm].[TransactionLogs] Script Date: 16.11.2018 14:49:57 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [tm].[TransactionLogs](
 [id] [int] IDENTITY(1,1) NOT NULL,
 [transaction_id] [int] NOT NULL,
 [price] [decimal](18, 2) NULL,
 [transaction_status_id] [varchar](8) NULL,
 [budget_year] [int] NULL,
 [additional_price] [decimal](18, 2) NOT NULL,
 [period_from] [datetime] NOT NULL,
 [period_to] [datetime] NOT NULL,
 [comment] [nvarchar](max) NULL,
 [created_by] [varchar](70) NULL,
 [created_at] [datetime] NOT NULL,
 [total_hours] [int] NOT NULL,
 CONSTRAINT [PK_TransactionLogs] PRIMARY KEY CLUSTERED 
(
 [id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO

ALTER TABLE [tm].[TransactionLogs] ADD DEFAULT ((0)) FOR [total_hours]
GO

ALTER TABLE [tm].[TransactionLogs] WITH CHECK ADD CONSTRAINT [FK_TransactionLogs_Employees_created_by] FOREIGN KEY([created_by])
REFERENCES [tm].[Employees] ([id])
GO

ALTER TABLE [tm].[TransactionLogs] CHECK CONSTRAINT [FK_TransactionLogs_Employees_created_by]
GO

ALTER TABLE [tm].[TransactionLogs] WITH CHECK ADD CONSTRAINT [FK_TransactionLogs_Transactions_transaction_id] FOREIGN KEY([transaction_id])
REFERENCES [tm].[Transactions] ([id])
ON DELETE CASCADE
GO

ALTER TABLE [tm].[TransactionLogs] CHECK CONSTRAINT [FK_TransactionLogs_Transactions_transaction_id]
GO

ALTER TABLE [tm].[TransactionLogs] WITH CHECK ADD CONSTRAINT [FK_TransactionLogs_TransactionStatuses_transaction_status_id] FOREIGN KEY([transaction_status_id])
REFERENCES [tm].[TransactionStatuses] ([id])
GO

ALTER TABLE [tm].[TransactionLogs] CHECK CONSTRAINT [FK_TransactionLogs_TransactionStatuses_transaction_status_id]
GO

db.TransactionLogs.OrderByDescending(x=> x.Id)
 .First(x => x.TransactionId == a.Id)
 .CreatedAt

Something's wrong with Linq Last, so I ordered it in opposite and used First. Everything is okey now. :)