diff --git a/frappe/deferred_insert.py b/frappe/deferred_insert.py
index 48f8ddae26..28c77002f8 100644
--- a/frappe/deferred_insert.py
+++ b/frappe/deferred_insert.py
@@ -1,13 +1,28 @@
 import json
+from typing import TYPE_CHECKING, Dict, List, Union
+
+import redis
 
 import frappe
 from frappe.utils import cstr
 
+if TYPE_CHECKING:
+	from frappe.model.document import Document
+
 queue_prefix = "insert_queue_for_"
 
 
-def deferred_insert(doctype, records):
-	frappe.cache().rpush(queue_prefix + doctype, records)
+def deferred_insert(doctype: str, records: Union[List[Union[Dict, "Document"]], str]):
+	if isinstance(records, (dict, list)):
+		_records = json.dumps(records)
+	else:
+		_records = records
+
+	try:
+		frappe.cache().rpush(f"{queue_prefix}{doctype}", _records)
+	except redis.exceptions.ConnectionError:
+		for record in records:
+			insert_record(record, doctype)
 
 
 def save_to_db():
@@ -30,19 +45,17 @@ def save_to_db():
 	frappe.db.commit()
 
 
-def insert_record(record, doctype):
-	if not record.get("doctype"):
-		record["doctype"] = doctype
+def insert_record(record: Union[Dict, "Document"], doctype: str):
+	setattr(record, "doctype", doctype)
 	try:
-		doc = frappe.get_doc(record)
-		doc.insert()
+		frappe.get_doc(record).insert()
 	except Exception as e:
-		print(e, doctype)
+		frappe.logger().error(f"Error while inserting deferred {doctype} record: {e}")
 
 
-def get_key_name(key):
+def get_key_name(key: str) -> str:
 	return cstr(key).split("|")[1]
 
 
-def get_doctype_name(key):
+def get_doctype_name(key: str) -> str:
 	return cstr(key).split(queue_prefix)[1]
diff --git a/frappe/desk/doctype/route_history/route_history.py b/frappe/desk/doctype/route_history/route_history.py
index cea1ed79e3..e712a5bb11 100644
--- a/frappe/desk/doctype/route_history/route_history.py
+++ b/frappe/desk/doctype/route_history/route_history.py
@@ -1,11 +1,11 @@
-# Copyright (c) 2021, Frappe Technologies and contributors
+# Copyright (c) 2022, Frappe Technologies and contributors
 # License: MIT. See LICENSE
 
-import json
-
 import frappe
 from frappe.deferred_insert import deferred_insert as _deferred_insert
 from frappe.model.document import Document
+from frappe.query_builder import DocType
+from frappe.query_builder.functions import Count
 
 
 class RouteHistory(Document):
@@ -14,31 +14,29 @@ class RouteHistory(Document):
 
 def flush_old_route_records():
 	"""Deletes all route records except last 500 records per user"""
-
 	records_to_keep_limit = 500
-	users = frappe.db.sql(
-		"""
-		SELECT `user`
-		FROM `tabRoute History`
-		GROUP BY `user`
-		HAVING count(`name`) > %(limit)s
-	""",
-		{"limit": records_to_keep_limit},
-	)
+	RouteHistory = DocType("Route History")
+
+	users = (
+		frappe.qb.from_(RouteHistory)
+		.select(RouteHistory.user)
+		.groupby(RouteHistory.user)
+		.having(Count(RouteHistory.name) > records_to_keep_limit)
+	).run(pluck=True)
 
 	for user in users:
-		user = user[0]
-		last_record_to_keep = frappe.db.get_all(
+		last_record_to_keep = frappe.get_all(
 			"Route History",
 			filters={"user": user},
-			limit=1,
 			limit_start=500,
 			fields=["modified"],
 			order_by="modified desc",
+			limit=1,
 		)
 
 		frappe.db.delete(
-			"Route History", {"modified": ("<=", last_record_to_keep[0].modified), "user": user}
+			"Route History",
+			{"modified": ("<=", last_record_to_keep[0].modified), "user": user},
 		)
 
 
@@ -53,7 +51,7 @@ def deferred_insert(routes):
 		for route in frappe.parse_json(routes)
 	]
 
-	_deferred_insert("Route History", json.dumps(routes))
+	_deferred_insert("Route History", routes)
 
 
 @frappe.whitelist()