From 8f2429ff24feeec6ddcf0f20f125aa35ebced0c9 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Fri, 1 May 2026 13:10:42 +0900
Subject: [PATCH] doc: Mention validation attempt during ALTER INDEX .. ATTACH
 PARTITION

Since 9d3e094f12, the command tries to validate the parent index of the
named index, if invalid.  The documentation did not mention this
behavior, which could be confusing.

Author: Mohamed ALi <moali.pg@gmail.com>
Discussion: https://postgr.es/m/CAGnOmWpHu25_LpT=zv7KtetQhqV1QEZzFYLd_TDyOLu1Od9fpw@mail.gmail.com
Backpatch-through: 14
---
 doc/src/sgml/ref/alter_index.sgml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/doc/src/sgml/ref/alter_index.sgml b/doc/src/sgml/ref/alter_index.sgml
index 1d42d05d858..fb7096c16ea 100644
--- a/doc/src/sgml/ref/alter_index.sgml
+++ b/doc/src/sgml/ref/alter_index.sgml
@@ -97,6 +97,11 @@ ALTER INDEX ALL IN TABLESPACE <replaceable class="parameter">name</replaceable>
       index cannot be dropped by itself, and will automatically be dropped
       if its parent index is dropped.
      </para>
+     <para>
+      If the named index is already attached to the altered index, the
+      command will attempt to validate the parent index if the parent is
+      currently invalid.
+     </para>
     </listitem>
    </varlistentry>