Migrate employee field to timesheet only if it exists in time log
diff --git a/erpnext/patches/v7_0/update_missing_employee_in_timesheet.py b/erpnext/patches/v7_0/update_missing_employee_in_timesheet.py
index 57f5189..54d492b 100644
--- a/erpnext/patches/v7_0/update_missing_employee_in_timesheet.py
+++ b/erpnext/patches/v7_0/update_missing_employee_in_timesheet.py
@@ -2,7 +2,7 @@
 import frappe
 
 def execute():
-	if frappe.db.table_exists("Time Log"):
+	if frappe.db.table_exists("Time Log") and "employee" in frappe.db.get_table_columns("Time Log"):
 		timesheet = frappe.db.sql("""select tl.employee as employee, ts.name as name,
 				tl.modified as modified, tl.modified_by as modified_by, tl.creation as creation, tl.owner as owner
 			from