Does importing a private key into QT overwrite existing bitcoins?

[josiahgarber]

Just wondering if I import a private key into QT whether it will add to the balance or replace it?  I am almost sure it adds to it, but was just wondering.  Yes I backed up my wallet.dat. :-)

Thanks.

[laanwj]

No, it only adds.

[josiahgarber]

That's what I thought.  Thanks for the help.  I thought it would be best to check.