Document how to identify an invalid index after a failed CREATE INDEX

CONCURRENTLY.

Gregory Stark

doc/src/sgml/ref/create_index.sgml

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-$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.60 2007/01/31 23:26:03 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_index.sgml,v 1.61 2007/04/03 22:38:35 momjian Exp $
 PostgreSQL documentation
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@@ -332,7 +332,20 @@ CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] <replaceable class="parameter">name</re
     uniqueness violation in a unique index, the <command>CREATE INDEX</>
     command will fail but leave behind an <quote>invalid</> index. This index
     will be ignored for querying purposes because it might be incomplete;
-    however it will still consume update overhead.  The recommended recovery
+    however it will still consume update overhead. The <application>psql</>
+    <command>\d</> command will mark such an index as <literal>INVALID</>:
+
+<programlisting>
+postgres=# \d tab
+       Table "public.tab"
+ Column |  Type   | Modifiers 
+--------+---------+-----------
+ col    | integer | 
+Indexes:
+    "idx" btree (col) INVALID
+</programlisting>
+
+    The recommended recovery
     method in such cases is to drop the index and try again to perform
     <command>CREATE INDEX CONCURRENTLY</>.  (Another possibility is to rebuild
     the index with <command>REINDEX</>.  However, since <command>REINDEX</>