docs: add mention of index swapping

Backpatch to 9.3

Greg Smith

diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml
index ca1e82018f9a1e935ebf4e05bf799a909c9de8e1..ae6456bc45ec701712ef1a53389c23ba2217186a 100644 (file)
--- a/doc/src/sgml/maintenance.sgml
+++ b/doc/src/sgml/maintenance.sgml
@@ -750,8 +750,9 @@ analyze threshold = analyze base threshold + analyze scale factor * number of tu
 
   
    In some situations it is worthwhile to rebuild indexes periodically
-   with the 
-   command.
+   with the  command or a series of individual
+   rebuilding steps.
+
   
 
   
@@ -777,6 +778,23 @@ analyze threshold = analyze base threshold + analyze scale factor * number of tu
    (This consideration does not apply to non-B-tree indexes.)  It
    might be worthwhile to reindex periodically just to improve access speed.
   
+
+  
+    can be used safely and easily in all cases.
+   But since the command requires an exclusive table lock, it is
+   often preferable to execute an index rebuild with a sequence of
+   creation and replacement steps.  Index types that support
+    with the CONCURRENTLY
+   option can instead be recreated that way. If that is successful and the
+   resulting index is valid, the original index can then be replaced by
+   the newly built one using a combination of 
+   and . When an index is used to enforce
+   uniqueness or other constraints,  might
+   be necessary to swap the existing constraint with one enforced by
+   the new index. Review this alternate multi-step rebuild approach
+   carefully before using it as there are limitations on which
+   indexes can be reindexed this way, and errors must be handled.
+  
  
 
 

diff --git a/doc/src/sgml/ref/create_index.sgml b/doc/src/sgml/ref/create_index.sgml
index 01faa3afcf78bd2feb3255c4db18e994ff11e38e..9a6a683e12d41c7928568a5b00348174f3225c1d 100644 (file)
--- a/doc/src/sgml/ref/create_index.sgml
+++ b/doc/src/sgml/ref/create_index.sgml
@@ -405,7 +405,7 @@ CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ name
    
 
    
-    If a problem arises while scanning the table, such as a
+    If a problem arises while scanning the table, such as a deadlock or a
     uniqueness violation in a unique index, the CREATE INDEX
     command will fail but leave behind an invalid index. This index
     will be ignored for querying purposes because it might be incomplete;