diff --git a/frappe/permissions.py b/frappe/permissions.py
index c1483b9b90..2589893072 100644
--- a/frappe/permissions.py
+++ b/frappe/permissions.py
@@ -97,7 +97,7 @@ def has_permission(doctype, ptype="read", doc=None, verbose=False, user=None, ra
 	if not perm:
 		perm = false_if_not_shared()
 
-	return perm
+	return bool(perm)
 
 def get_doc_permissions(doc, user=None, ptype=None):
 	"""Returns a dict of evaluated permissions for given `doc` like `{"read":1, "write":1}`"""
@@ -592,10 +592,7 @@ def has_child_table_permission(child_doctype, ptype="read", child_doc=None,
 
 
 def is_parent_valid(child_doctype, parent_doctype):
-	filters = {
-		"options": child_doctype,
-		"fieldtype": "Table",
-		"parent": parent_doctype
-	}
-	return not frappe.is_table(parent_doctype) and (frappe.db.exists("DocField", filters, cache=True)
-			or frappe.db.exists("Custom Field", filters, cache=True))
\ No newline at end of file
+	from frappe.core.utils import find
+	parent_meta = frappe.get_meta(parent_doctype)
+	child_table_field_exist = find(parent_meta.get_table_fields(), lambda d: d.options == child_doctype)
+	return not frappe.is_table(parent_doctype) and child_table_field_exist
\ No newline at end of file