function dbn=web_db_modfields(db,oldField,newField)

noldFields=length(oldField);
nnewFields=length(newField);
numRec=length(db);

% creat the new db
for irec=1:numRec
for i=1:nnewFields
	str=['dbn(irec).',newField{i},'={''n/a ',newField{i},'''};'];
	eval(str);
end
end

ikeep=[];
for i=1:noldFields
	if isfield(dbn(1), oldField{i})
		ikeep=[ikeep i];
	end
end

oldField=oldField(ikeep);
noldFields=length(oldField);

for irec=1:numRec
	for i=1:noldFields
		str=['dbn(irec).',oldField{i},'=db(irec).',oldField{i},';'];
		eval(str);
	end
end