SQL column default value with Entity Framework

Question

I am trying to use Code-First EF6 with default SQL values.

For example, I have a \"CreatedDate\" column/property not null with a default in SQL of \"getdate()\"

Answer 1

[mysql]

For those, who don't want to use computed and rewrite it after every db update, I wrote extension method for database partial class. Sure, there are thing that has to be improved or added, but for now it is enough for our using, enjoy.

Take into account, that due to database_schema access it is not the fastest and also you need to have same entity name as table name (or rewrite it somehow).

    public static bool GetDBDefaults(object entity)
    {
        try
        {
            string table_name = entity.GetType().Name;

            string q = $"select column_name, column_default from information_schema.columns where column_default is not null and table_schema not in ('information_schema', 'sys', 'performance_schema', 'mysql') and table_name = '{table_name}' order by table_schema, table_name, ordinal_position;";

            List dbDefaults = new List();
            using (DatabaseModelFull db = new DatabaseModelFull())
            {
                dbDefaults = db.Database.SqlQuery(q).ToList();
            }

            Type myType = entity.GetType();
            IList props = new List(myType.GetProperties());
            IList fields = new List(myType.GetFields());

            foreach (var dbDefault in dbDefaults)
            {
                var prop = props.SingleOrDefault(x => x.Name == dbDefault.column_name);

                if (prop != null)
                {
                    if (dbDefault.column_default.Equals("CURRENT_TIMESTAMP"))
                        prop.SetValue(entity, System.Convert.ChangeType(DateTime.Now, prop.PropertyType));
                    else
                        prop.SetValue(entity, System.Convert.ChangeType(dbDefault.column_default, prop.PropertyType));
                    continue;
                }

                var field = fields.SingleOrDefault(x => x.Name == dbDefault.column_name);

                if (field != null)
                {
                    if (dbDefault.column_default.Equals("CURRENT_TIMESTAMP"))
                        field.SetValue(entity, System.Convert.ChangeType(DateTime.Now, field.FieldType));
                    else
                        field.SetValue(entity, System.Convert.ChangeType(dbDefault.column_default, field.FieldType));
                }
            }
            return true;
        }
        catch
        {
            return false;
        }
    }


    public class DBDefaults
    {
        public string column_name { get; set; }
        public string column_default { get; set; }
    }