diff --git a/erpnext/accounts/report/item_wise_purchase_register/item_wise_purchase_register.py b/erpnext/accounts/report/item_wise_purchase_register/item_wise_purchase_register.py
index 559ba4a70ab..c9d37b9ad1a 100644
--- a/erpnext/accounts/report/item_wise_purchase_register/item_wise_purchase_register.py
+++ b/erpnext/accounts/report/item_wise_purchase_register/item_wise_purchase_register.py
@@ -310,8 +310,8 @@ def apply_conditions(query, pi, pii, filters):
 
 def get_items(filters, additional_table_columns):
 	doctype = "Purchase Invoice"
-	pi = frappe.qb.DocType(doctype).as_("invoice")
-	pii = frappe.qb.DocType(f"{doctype} Item").as_("invoice_item")
+	pi = frappe.qb.DocType("Purchase Invoice")
+	pii = frappe.qb.DocType("Purchase Invoice Item")
 	Item = frappe.qb.DocType("Item")
 	query = (
 		frappe.qb.from_(pi)
@@ -375,7 +375,7 @@ def get_items(filters, additional_table_columns):
 	if match_conditions:
 		query += " and " + match_conditions
 
-	query = apply_order_by_conditions(query, filters)
+	query = apply_order_by_conditions(doctype, query, filters)
 
 	return frappe.db.sql(query, params, as_dict=True)
 
diff --git a/erpnext/accounts/report/item_wise_sales_register/item_wise_sales_register.py b/erpnext/accounts/report/item_wise_sales_register/item_wise_sales_register.py
index b4a72c5374f..073efdadb6a 100644
--- a/erpnext/accounts/report/item_wise_sales_register/item_wise_sales_register.py
+++ b/erpnext/accounts/report/item_wise_sales_register/item_wise_sales_register.py
@@ -394,15 +394,18 @@ def apply_conditions(query, si, sii, sip, filters, additional_conditions=None):
 	return query
 
 
-def apply_order_by_conditions(query, filters):
+def apply_order_by_conditions(doctype, query, filters):
+	invoice = f"`tab{doctype}`"
+	invoice_item = f"`tab{doctype} Item`"
+
 	if not filters.get("group_by"):
-		query += "order by invoice.posting_date desc, invoice_item.item_group desc"
+		query += f" order by {invoice}.posting_date desc, {invoice_item}.item_group desc"
 	elif filters.get("group_by") == "Invoice":
-		query += "order by invoice_item.parent desc"
+		query += f" order by {invoice_item}.parent desc"
 	elif filters.get("group_by") == "Item":
-		query += "order by invoice_item.item_code"
+		query += f" order by {invoice_item}.item_code"
 	elif filters.get("group_by") == "Item Group":
-		query += "order by invoice_item.item_group"
+		query += f" order by {invoice_item}.item_group"
 	elif filters.get("group_by") in ("Customer", "Customer Group", "Territory", "Supplier"):
 		filter_field = frappe.scrub(filters.get("group_by"))
 		query += f" order by {filter_field} desc"
@@ -412,8 +415,8 @@ def apply_order_by_conditions(query, filters):
 
 def get_items(filters, additional_query_columns, additional_conditions=None):
 	doctype = "Sales Invoice"
-	si = frappe.qb.DocType("Sales Invoice").as_("invoice")
-	sii = frappe.qb.DocType("Sales Invoice Item").as_("invoice_item")
+	si = frappe.qb.DocType("Sales Invoice")
+	sii = frappe.qb.DocType("Sales Invoice Item")
 	sip = frappe.qb.DocType("Sales Invoice Payment")
 	item = frappe.qb.DocType("Item")
 
@@ -487,12 +490,12 @@ def get_items(filters, additional_query_columns, additional_conditions=None):
 	from frappe.desk.reportview import build_match_conditions
 
 	query, params = query.walk()
-	match_conditions = build_match_conditions("Sales Invoice")
+	match_conditions = build_match_conditions(doctype)
 
 	if match_conditions:
 		query += " and " + match_conditions
 
-	query = apply_order_by_conditions(query, filters)
+	query = apply_order_by_conditions(doctype, query, filters)
 
 	return frappe.db.sql(query, params, as_dict=True)