diff --git a/db_presto.nim b/db_presto.nim
index bcc3b5c..21f5e4c 100644
--- a/db_presto.nim
+++ b/db_presto.nim
@@ -1,4 +1,5 @@
 import httpclient, base64, json, strutils, sequtils
+export json
 
 type
   CursorAlreadyClosedException = object of Exception
@@ -99,7 +100,7 @@ proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string =
   var a = 0
   for c in items(string(formatstr)):
     if c == '?':
-      if args[a] == nil:
+      if args[a] == "":
         add(result, "NULL")
       else:
         add(result, dbQuote(args[a]))
diff --git a/db_presto.nimble b/db_presto.nimble
index 0c66e1d..77b80c8 100644
--- a/db_presto.nimble
+++ b/db_presto.nimble
@@ -1,11 +1,11 @@
 # Package
 
-version       = "1.0.1"
+version       = "1.1.0"
 author        = "Bennyelg"
 description   = "prestodb connector"
 license       = "MIT"
 skipDirs = @["tests"]
 # Dependencies
 
-requires "nim >= 0.17.2"
+requires "nim >= 0.18.0"