Clarify description of covering indexes in release notes

diff --git a/doc/src/sgml/release-9.2.sgml b/doc/src/sgml/release-9.2.sgml
index a842d448e9ebe510e17f20af2f6492c592633408..ce368e90988636be92baf9a3733cfab437b6a3fa 100644 (file)
--- a/doc/src/sgml/release-9.2.sgml
+++ b/doc/src/sgml/release-9.2.sgml
@@ -425,7 +425,8 @@
        
 
        
-        This is often called "index-only scans" or "covering indexes".
+        This is often called "index-only scans", a feature which now enables
+        the use of indexes with additional columns, or "covering indexes".
         This is possible for heap pages with exclusively all-visible
         tuples, as reported by the visibility map.  The visibility map was
         made crash-safe as a necessary part of implementing this feature.