Entity framework Update entry duplicate key-CodePudding

I have an entity like this:

public class Notification
{
    public int Id { get; set; }
    public bool IsReminderActive { get; set; }
    public bool IsInvitationActive { get; set; }
    public int ContractId { get; set; }
    public bool IsActive { get; set; }
}

And if I want to update a entry or create a new one I'm trying something like this:

public async Task<bool> Post(Notification notificationEmail)
    {
        try
        {
            if (!_context.Notification.Any(x => x.ContractId == notificationEmail.ContractId))
            {
                _logger.LogInformation($"Creating new Notification for contract {notificationEmailType.ContractId}");
                _context.Notification.Add(notificationEmail);
            }
            else
            {
                var update = _context.Notification.First(x => x.ContractId == notificationEmail.ContractId);
                update.IsInvitationActive = notificationEmail.IsInvitationActive;
                update.IsReminderActive = notificationEmail.IsReminderActive;
                _logger.LogInformation($"Updating Notification for contract {notificationEmail.ContractId}");
                _context.Notification.Update(update);
            }
            await _context.SaveChangesAsync();
        }
        catch (Exception ex)
        {
            _logger.LogError("Error trying to create/update Notification", ex);
            return false;
        }
        return true;
    }

I did the update part like that because if I try to update the entry with the notificationEmail variable, I had an error of duplicate key for ContractId.

SqlException: Cannot insert duplicate key row in object 'dbo.Notification' with unique index 'IX_Notification_ContractId'. The duplicate key value is (4).

There is a better way of writing the update code?

CodePudding user response：

First of all you should move the Update code on a PUT or a PATCH Request, then you don't need to pass the id to the post when you create a new record

CodePudding user response：

Yes, you don't need to call Update() because you already have a tracked instance when you use _context.Notification.First. Just attempt to get a tracked instance initially then update it if found.

    public async Task<bool> Post(Notification notificationEmail)
    {
        try
        {
            var notification = _context.Notification.FirstOrDefault(x => x.ContractId == notificationEmail.ContractId);
            if (notification == null)
            {
                _logger.LogInformation($"Creating new Notification for contract {notificationEmailType.ContractId}");
                _context.Notification.Add(notificationEmail);
            }
            else
            {
                notification.IsInvitationActive = notificationEmail.IsInvitationActive;
                notification.IsReminderActive = notificationEmail.IsReminderActive;
                _logger.LogInformation($"Updating Notification for contract {notificationEmail.ContractId}");
            }
            await _context.SaveChangesAsync();
        }
        catch (Exception ex)
        {
            _logger.LogError("Error trying to create/update Notification", ex);
            return false;
        }
        return true;