I have got a pretty fat settings table in SQL Server 2012, now with over 100 columns. As the name suggests, this table keeps track of all kinds of setting values within our website. It used to be having less than 50 columns but now its size is doubled.
The reason why I store setting values into database is because users will need to have ability to change these settings via UI.
Should I really be worried about this table getting bigger and bigger over time? Or I will have to find some other ways to store settings data, e.g save into files, perhaps?
First, you don't need to store settings in a database in order to update them at runtime by users. You can simply store them in a settings file that gets updated whenever the user makes changes. This is an xml config file and works well.
If, however, the application is network based, and you want the settings to follow the user from machine to machine, it makes more sense to put it in a database.
Second, yes... 100 columns is huge. Instead of storing each setting in a separate column, you might consider storing each setting in a separate row, and then have a common row format which is ID, SettingName, SettingValue, (maybe) DefaultValue. Then your table can grow as large as you like.