修改find

src/mongodb/mongodb.go

@@ -592,9 +592,10 @@ func (m *MongodbSim) Find(c string, query interface{}, order interface{}, fields
 	defer catch()
 	m.Open()
 	defer m.Close()
-	res := make([]map[string]interface{}, 1)
+	var res []map[string]interface{}
 	coll := m.C.Database(m.DbName).Collection(c)
 	if single {
+		res = make([]map[string]interface{}, 1)
 		of := options.FindOne()
 		of.SetProjection(ObjToOth(fields))
 		of.SetSort(ObjToM(order))
@@ -602,6 +603,7 @@ func (m *MongodbSim) Find(c string, query interface{}, order interface{}, fields
 			sr.Decode(&res[0])
 		}
 	} else {
+		res = []map[string]interface{}{}
 		of := options.Find()
 		of.SetProjection(ObjToOth(fields))
 		of.SetSort(ObjToM(order))