From 499787819309293f3d2cd7219aee334a0e7d5069 Mon Sep 17 00:00:00 2001
From: Tom Lane
Date: Fri, 12 Aug 2016 18:45:18 -0400
Subject: Doc: clarify that DROP ... CASCADE is recursive.

Apparently that's not obvious to everybody, so let's belabor the point.

In passing, document that DROP POLICY has CASCADE/RESTRICT options (which
it does, per gram.y) but they do nothing (I assume, anyway).  Also update
some long-obsolete commentary in gram.y.

Discussion: <20160805104837.1412.84915@wrigleys.postgresql.org>
---
 src/backend/parser/gram.y | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

(limited to 'src')

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 0cae44641f8..6a0f7b393cb 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -1126,9 +1126,9 @@ AlterUserSetStmt:
  *
  * Drop a postgresql DBMS role
  *
- * XXX Ideally this would have CASCADE/RESTRICT options, but since a role
- * might own objects in multiple databases, there is presently no way to
- * implement either cascading or restricting.  Caveat DBA.
+ * XXX Ideally this would have CASCADE/RESTRICT options, but a role
+ * might own objects in multiple databases, and there is presently no way to
+ * implement cascading to other databases.  So we always behave as RESTRICT.
  *****************************************************************************/
 
 DropRoleStmt:
@@ -1152,9 +1152,7 @@ DropRoleStmt:
  *
  * Drop a postgresql DBMS user
  *
- * XXX Ideally this would have CASCADE/RESTRICT options, but since a user
- * might own objects in multiple databases, there is presently no way to
- * implement either cascading or restricting.  Caveat DBA.
+ * XXX As with DROP ROLE, no CASCADE/RESTRICT here.
  *****************************************************************************/
 
 DropUserStmt:
@@ -1220,7 +1218,7 @@ add_drop:	ADD_P									{ $$ = +1; }
  *
  * Drop a postgresql group
  *
- * XXX see above notes about cascading DROP USER; groups have same problem.
+ * XXX As with DROP ROLE, no CASCADE/RESTRICT here.
  *****************************************************************************/
 
 DropGroupStmt:
@@ -4574,6 +4572,8 @@ auth_ident: RoleSpec			{ $$ = $1; }
  *		QUERY :
  *				DROP USER MAPPING FOR auth_ident SERVER name
  *
+ * XXX you'd think this should have a CASCADE/RESTRICT option, even if it's
+ * only pro forma; but the SQL standard doesn't show one.
  ****************************************************************************/
 
 DropUserMappingStmt: DROP USER MAPPING FOR auth_ident SERVER name
-- 
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