v2-0001-Reject-invalid-databases-in-pg_get_database_ddl.patch

application/octet-stream

Filename: v2-0001-Reject-invalid-databases-in-pg_get_database_ddl.patch
Type: application/octet-stream
Part: 0
Message: Re: Reject invalid databases in pg_get_database_ddl()

Patch

Same data as JSON: GET /api/v1/attachments/:id/patch the parsed metadata as JSON — format, series position, per-file stats; never the diff bytes. API reference →
Format: format-patch
Series: patch v2-0001
Subject: Reject invalid databases in pg_get_database_ddl()
File+
src/backend/utils/adt/ddlutils.c 11 0
From ca98087734df0cddefd9610b7c23be8d1b758969 Mon Sep 17 00:00:00 2001
From: Amit Langote <amitlan@postgresql.org>
Date: Fri, 17 Apr 2026 08:42:19 +0900
Subject: [PATCH v2] Reject invalid databases in pg_get_database_ddl()

An invalid database has datconnlimit set to -2.  pg_get_database_ddl()
emits this verbatim as CONNECTION LIMIT = -2, which ALTER DATABASE
rejects.  Error out early instead.

Reported-by: Lakshmi N <lakshmin.jhs@gmail.com>
Author: Lakshmi N <lakshmin.jhs@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+3i_M8m1k2gFch+tU0JmAQh9FRV+pFrfTXDrJo+BqmwsTmOhg@mail.gmail.com
---
 src/backend/utils/adt/ddlutils.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/backend/utils/adt/ddlutils.c b/src/backend/utils/adt/ddlutils.c
index c4f9f86c43e..3921ed1fa6a 100644
--- a/src/backend/utils/adt/ddlutils.c
+++ b/src/backend/utils/adt/ddlutils.c
@@ -887,6 +887,17 @@ pg_get_database_ddl_internal(Oid dbid, bool pretty,
 	dbform = (Form_pg_database) GETSTRUCT(tuple);
 	dbname = pstrdup(NameStr(dbform->datname));
 
+	/*
+	 * Reject invalid databases: datconnlimit = -2 would be emitted as
+	 * CONNECTION LIMIT = -2, which cannot be executed.
+	 */
+	if (database_is_invalid_form(dbform))
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot generate DDL for invalid database \"%s\"",
+						dbname),
+				 errhint("Use DROP DATABASE to drop invalid databases.")));
+
 	/*
 	 * We don't support generating DDL for system databases.  The primary
 	 * reason for this is that users shouldn't be recreating them.
-- 
2.47.3