validate pricing rule discount with item max discount
diff --git a/erpnext/accounts/doctype/pricing_rule/pricing_rule.py b/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
index c86e3f6..77b52b1 100644
--- a/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
+++ b/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
@@ -65,7 +65,7 @@
 	def validate_max_discount(self):
 		if self.price_or_discount == "Discount Percentage" and self.item_code:
 			max_discount = frappe.db.get_value("Item", self.item_code, "max_discount")
-			if flt(self.discount_percentage) > max_discount:
+			if max_discount and flt(self.discount_percentage) > flt(max_discount):
 				throw(_("Max discount allowed for item: {0} is {1}%".format(self.item_code, max_discount)))