Remove field from all docs in a CouchDB database

gistfile1.js

console.log("Fetching docs...");
var j = 0;
var docs = [];
var ids = [];
var startdoc = '0';
function fetchdocs(startdocthistime){
    nano.list({ stale: "ok", startkey:startdocthistime, limit:1000, include_docs:true}, function(err, data, headers){ 
	console.log("Updating " + data.rows.length + " docs...");
	for (var i = 0; i < data.rows.length; i++) {
		ids.push(data.rows[i].id);
                if (data.rows[i].doc.metadata && data.rows[i].doc..metadata.host) {
		delete data.rows[i].doc.metadata['host'];
		delete data.rows[i].doc.metadata['content-type'];
		delete data.rows[i].doc.metadata['x-forwarded-proto'];
		delete data.rows[i].doc.metadata['x-forwarded-port'];
		delete data.rows[i].doc.metadata['content-length'];
		delete data.rows[i].doc.metadata['connection'];
		delete data.rows[i].doc.metadata['request-time'];
		delete data.rows[i].doc.metadata['accept-encoding'];
		delete data.rows[i].doc.metadata['cookie'];
		docs.push(data.rows[i].doc);
                startdoc = data.rows[i].id;
                delete data.rows[i];
		}
	}
        delete data; // free up some memory.
        fetchdocs(startdoc);
        return true;
    });
    return true;
}

fetchdocs(startdoc);

setInterval(function() {
	var batch = docs.splice(0, 1000);
	if (batch.length > 0) {
	//console.log("Processing batch of size ", batch.length);
	nano.bulk({ docs: batch }, function(error, body, headers) {
		//console.log("Got a response");
		if (error) { 
			console.log(error);
			errors = errors.concat(batch);
		} else { 
			console.log("Altered " + batch.length + " docs"); 
			//console.log(body);
		}
	});
	}
}, 5000);