diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
new file mode 100644
index 92e9ce8..784f5b4
*** a/doc/src/sgml/ref/alter_table.sgml
--- b/doc/src/sgml/ref/alter_table.sgml
*************** ALTER TABLE ALL IN TABLESPACE <replaceab
*** 320,327 ****
         Adding a constraint using an existing index can be helpful in
         situations where a new constraint needs to be added without blocking
         table updates for a long time.  To do that, create the index using
!        <command>CREATE INDEX CONCURRENTLY</>, and then install it as an
!        official constraint using this syntax.  See the example below.
        </para>
       </note>
      </listitem>
--- 320,327 ----
         Adding a constraint using an existing index can be helpful in
         situations where a new constraint needs to be added without blocking
         table updates for a long time.  To do that, create the index using
!        <command>CREATE UNIQUE INDEX CONCURRENTLY</>, and then convert it to a
!        constraint using this syntax.  See the example below.
        </para>
       </note>
      </listitem>