diff --git a/erpnext/stock/doctype/delivery_note/delivery_note.py b/erpnext/stock/doctype/delivery_note/delivery_note.py
index 9ee1802..c3247fb 100644
--- a/erpnext/stock/doctype/delivery_note/delivery_note.py
+++ b/erpnext/stock/doctype/delivery_note/delivery_note.py
@@ -339,27 +339,35 @@
 			frappe.throw(_("Could not create Credit Note automatically, please uncheck 'Issue Credit Note' and submit again"))
 
 def update_billed_amount_based_on_so(so_detail, update_modified=True):
+	from frappe.query_builder.functions import Sum
+
 	# Billed against Sales Order directly
-	billed_against_so = frappe.db.sql("""select sum(si_item.amount)
-		from `tabSales Invoice Item` si_item, `tabSales Invoice` si
-		where
-			si_item.parent = si.name
-			and si_item.so_detail=%s
-			and (si_item.dn_detail is null or si_item.dn_detail = '')
-			and si_item.docstatus=1
-			and si.update_stock = 0
-		""", so_detail)
+	si = frappe.qb.DocType("Sales Invoice").as_("si")
+	si_item = frappe.qb.DocType("Sales Invoice Item").as_("si_item")
+	sum_amount = Sum(si_item.amount).as_("amount")
+
+	billed_against_so = frappe.qb.from_(si).from_(si_item).select(sum_amount).where(
+		(si_item.parent == si.name) &
+		(si_item.so_detail == so_detail) &
+		((si_item.dn_detail.isnull()) | (si_item.dn_detail == '')) &
+		(si_item.docstatus == 1) &
+		(si.update_stock == 0)
+	).run()
 	billed_against_so = billed_against_so and billed_against_so[0][0] or 0
 
 	# Get all Delivery Note Item rows against the Sales Order Item row
-	dn_details = frappe.db.sql("""select dn_item.name, dn_item.amount, dn_item.si_detail, dn_item.parent, dn_item.stock_qty, dn_item.returned_qty
-		from `tabDelivery Note Item` dn_item, `tabDelivery Note` dn
-		where
-			dn.name = dn_item.parent
-			and dn_item.so_detail=%s
-			and dn.docstatus=1
-			and dn.is_return = 0
-		order by dn.posting_date asc, dn.posting_time asc, dn.name asc""", so_detail, as_dict=1)
+
+	dn = frappe.qb.DocType("Delivery Note").as_("dn")
+	dn_item = frappe.qb.DocType("Delivery Note Item").as_("dn_item")
+
+	dn_details = frappe.qb.from_(dn).from_(dn_item).select(dn_item.name, dn_item.amount, dn_item.si_detail, dn_item.parent, dn_item.stock_qty, dn_item.returned_qty).where(
+		(dn.name == dn_item.parent) &
+		(dn_item.so_detail == so_detail) &
+		(dn.docstatus == 1) &
+		(dn.is_return == 0)
+	).orderby(
+		dn.posting_date, dn.posting_time, dn.name
+	).run(as_dict=True)
 
 	updated_dn = []
 	for dnd in dn_details: