diff --git a/erpnext/selling/doctype/customer/customer.py b/erpnext/selling/doctype/customer/customer.py
index 0dd60ae0b6..72ec1dce17 100644
--- a/erpnext/selling/doctype/customer/customer.py
+++ b/erpnext/selling/doctype/customer/customer.py
@@ -29,14 +29,14 @@ class Customer(TransactionBase):
 				frappe.throw(_("Series is mandatory"), frappe.MandatoryError)
 
 			self.name = make_autoname(self.naming_series+'.#####')
-			
+
 	def get_customer_name(self):
 		if frappe.db.get_value("Customer", self.customer_name):
 			count = frappe.db.sql("""select ifnull(max(SUBSTRING_INDEX(name, ' ', -1)), 0) from tabCustomer
-				 where name like  '%{0} - %'""".format(self.customer_name), as_list=1)[0][0]
+				 where name like %s""", "%{0} - %".format(self.customer_name), as_list=1)[0][0]
 			count = cint(count) + 1
 			return "{0} - {1}".format(self.customer_name, cstr(count))
-		
+
 		return self.customer_name
 
 	def validate(self):
@@ -234,4 +234,4 @@ def get_credit_limit(customer, company):
 		credit_limit = frappe.db.get_value("Customer Group", customer_group, "credit_limit") or \
 			frappe.db.get_value("Company", company, "credit_limit")
 
-	return credit_limit
\ No newline at end of file
+	return credit_limit