Database are used to store index ID used by the website for the show name.
Different websites use their own ID format for indexing the showname.
You are not required to enter every show before renaming.
theRenamer makes pretty good guesses of the showname.
After a renaming session, any new Show names that were guessed are automatically added into the database.
This is assuming that you will be renaming the same show following week.
Keep as little rows as possible, the more there is, the more theRenamer needs to compare with next time.
For instance, after you have renamed the last episode of 'Lost' , there's no point in keeping the info since the series has ended.
For any reason you need to rename again, theRenamer can still guess the IDcode for it.