Need Link Building Advice????

Hi i have a link building question means my friend are going for an interview they asked a question for link building that how much database u have used for link building my friend not get this point and they r not give any response for that question ....so can plz anybody tell me what is that question means how much database u have used for link building??????

 

data base for what.... we update data daily..... and there is thousand's websites come online daily in the market... then what is a limit of database.. ??

it's a stupid question

 

I don't think that is not good question for interview or he thought about another kind of database.

 

That question doesn't make sense. The only thing I can think of is I keep a list of all the websites I use to submit backlinks in an excel file, and I make a note when I add a link for a site. I could put that in a database.