I have a table that contains two not null columns Created and Updated.

I wrote corresponding triggers

ALTER TRIGGER [dbo].[tr_category_inserted] ON [dbo].[Category]

AFTER INSERT

AS

BEGIN

  UPDATE Category

  SET Created = GETDATE(), Updated = GETDATE()

  FROM inserted

  WHERE Category.ID = inserted.ID;

END

and

ALTER TRIGGER [dbo].[tr_category_updated] ON [dbo].[Category]

AFTER UPDATE

AS

BEGIN

  UPDATE Category

  SET Updated = GETDATE()

    FROM inserted

        inner join [dbo].[Category] c on c.ID = inserted.ID

END

but if I am inserting a new row I get an error

Cannot insert the value NULL into column 'Created', table 'Category'; column does not allow nulls. INSERT fails.

Insert command:

INSERT INTO [Category]([Name], [ShowInMenu], [Deleted])

     VALUES ('category1', 0, 0)

How can I write such triggers without a setting to these columns to allow null?