Laravel error with save()

Ok so I spent loads of time with this problem today which it is actually just a small problem(and it is a problem from my side)

I have trouble with $var->save(), with the error code 500.

And the biggest problem is that, using a RAW query is fine =.=

After going to start->global.php and turning on the error logging, apparently it is because I didn't create a created_by column when I create this new table. (Confirmed by checking BaseModel)

The purpose of this blog is mainly to tell myself that I can turn on error logging by visiting start->global.php