doc: mentioned CREATE+ATTACH PARTITION as an alternative to CREATE TABLE..PARTITION OF

[Justin Pryzby]

It's easy to use CREATE TABLE..LIKE + ALTER..ATTACH PARTITION to avoid
acquiring a strong lock when creating a new partition.
But it's also easy to forget.

commit 76c0d1198cf2908423b321cd3340d296cb668c8e
Author: Justin Pryzby <pryz...@telsasoft.com>
Date:   Mon Jul 18 09:24:55 2022 -0500

    doc: mention CREATE+ATTACH PARTITION as an alternative to CREATE 
TABLE..PARTITION OF
    
    See also: 898e5e3290a72d288923260143930fb32036c00c
    Should backpatch to v12

diff --git a/doc/src/sgml/ref/create_table.sgml 
b/doc/src/sgml/ref/create_table.sgml
index 6bbf15ed1a4..db7d8710bae 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -619,6 +619,16 @@ WITH ( MODULUS <replaceable 
class="parameter">numeric_literal</replaceable>, REM
       with <literal>DROP TABLE</literal> requires taking an <literal>ACCESS
       EXCLUSIVE</literal> lock on the parent table.
      </para>
+
+     <para>
+      Note that creating a partition acquires an <literal>ACCESS
+      EXCLUSIVE</literal> lock on the parent table.
+      It may be preferable to first CREATE a separate table and then ATTACH it,
+      which does not require as strong of a lock.
+      See <link linkend="sql-altertable-attach-partition">ATTACH 
PARTITION</link>
+      and <xref linkend="ddl-partitioning"/> for more information.
+     </para>
+
     </listitem>
    </varlistentry>