Clarify which relkinds accept column comments.

Per discussion with Josh Kupershmidt.

diff --git a/doc/src/sgml/ref/comment.sgml b/doc/src/sgml/ref/comment.sgml
index ab12614f8430b8a941eefe164a44efd59dd0c212..0b28d8eefc51454a2b828ffc11e28a7e96f376aa 100644 (file)
--- a/doc/src/sgml/ref/comment.sgml
+++ b/doc/src/sgml/ref/comment.sgml
@@ -26,7 +26,7 @@ COMMENT ON
   AGGREGATE agg_name (agg_type [, ...] ) |
   CAST (source_type AS target_type) |
   COLLATION object_name |
-  COLUMN table_name.column_name |
+  COLUMN relation_name.column_name |
   CONSTRAINT constraint_name ON table_name |
   CONVERSION object_name |
   DATABASE object_name |
@@ -98,7 +98,7 @@ COMMENT ON
   
    
     object_name
-    table_name.column_name
+    relation_name.column_name
     agg_name
     constraint_name
     function_name
@@ -111,6 +111,9 @@ COMMENT ON
       aggregates, collations, conversions, domains, foreign tables, functions,
       indexes, operators, operator classes, operator families, sequences,
       text search objects, types, and views can be schema-qualified.
+      When commenting on a column,
+      relation_name must refer
+      to a table, view, composite types, or foreign table.