Notwithstanding section 531 of this title, nothing contained in this title shall be construed to impair or affect the right of any claimant to maintain a personal action to recover his debt against the person liable therefor either in a separate action or in the action to foreclose his lien, nor any right he may have to the issuance of a writ of attachment or execution. The judgment, if any, obtained by the plaintiff in such personal action shall not impair or merge any lien held by the plaintiff under this chapter, but any money collected on such judgment shall be credited on the amount of such lien.