What is the player database size?

I know it makes there more players in the game but how? For example if I chose small database would players like, Messi, Ronaldo etc. be in the game? Also why are some players unsignable and have blacked out names on some teams?

When you pick small database, only those players in your league and players with high reputation would be loaded.. as you go up the sizes of database more players will be added also.. so with a large database you will have all the top european world class players etc ... you can also customise the database yourself using the custom option.

The blacked out names are fake players added to teams to make up the numbers in teams where your database wasn't large enough to add the real ones in.

Generally, the biggest stars will always be there, no matter database size.

Other than that, it all depends on which leagues you load and such.

The "grey" players are fake players that "fill up" teams that don't have enough actual players. You cannot sign those as they don't actually exist as such.