Again update C comments for pg_attribute.attislocal

diff --git a/src/include/catalog/pg_attribute.h b/src/include/catalog/pg_attribute.h
index 1bd42a8410fca60cf3a66539ff62076f6e4df322..391d5687730d59f16b7212f95c13c0ebdaba7f18 100644 (file)
--- a/src/include/catalog/pg_attribute.h
+++ b/src/include/catalog/pg_attribute.h
@@ -137,9 +137,13 @@ CATALOG(pg_attribute,1249) BKI_BOOTSTRAP BKI_WITHOUT_OIDS BKI_ROWTYPE_OID(75) BK
    bool        attisdropped;
 
    /*
-    * Has a local definition (hence, do not drop when attinhcount is 0)
-    * This is set and remains set if the column was _ever_
-    * local/not-inherited, e.g. this can be set by ALTER TABLE NO INHERIT.
+    * This flag specifies whether this column has ever had a local
+    * definition.  It is set for normal non-inherited columns, but also
+    * for columns that are inherited from parents if also explicitly listed
+    * in CREATE TABLE INHERITS.  It is also set when inheritance is removed
+    * from a table with ALTER TABLE NO INHERIT.  If the flag is set, the
+    * column is not dropped by a parent's DROP COLUMN even if this causes
+    * the column's attinhcount to become zero.
     */
    bool        attislocal;