diff --git a/src/postgrest.js b/src/postgrest.js
index 4523c0a..897178e 100644
--- a/src/postgrest.js
+++ b/src/postgrest.js
@@ -123,20 +123,19 @@ export default (api_root, auth={}) => {
 			if (options.queries) {
 				// build the query string
 				let _query_string = options.queries
-						.filter(query => typeof query != 'undefined')
 						.map(query => {
+							if (typeof query == 'undefined') return undefined
+
 							// prepare the query kv pair and optional operator
 							let k = query.label
 							let v = query.value
 							let op = query.op
 
-							// return early if v is empty
-							if (typeof v == 'undefined' || (!v && v !== 0))
-								return undefined
-
 							// generate value if v is a function
-							if (typeof v == 'function')
-								v = v()
+							if (typeof v == 'function') v = v()
+
+							// return early if v is empty
+							if (typeof v == 'undefined' || (!v && v !== 0)) return undefined
 
 							// format v on k & op
 							if (op == 'like')
@@ -152,6 +151,7 @@ export default (api_root, auth={}) => {
 
 							return {k: k, v: op ? `${op}.${v}` : v}
 						})
+						.filter(query => typeof query != 'undefined')
 						.map(query => query.k + '=' + encodeURIComponent(query.v)).join('&')
 
 				// append query string to url if necessary