Merge mysql.com:/home/timka/mysql/src/5.0-virgin

into  mysql.com:/home/timka/mysql/src/5.0-2486-merge


mysql-test/r/errors.result:
  Auto merged
mysql-test/r/fulltext.result:
  Auto merged
mysql-test/r/fulltext_order_by.result:
  Auto merged
mysql-test/r/innodb.result:
  Auto merged
mysql-test/r/join_nested.result:
  Auto merged
mysql-test/r/subselect.result:
  Auto merged
mysql-test/t/errors.test:
  Auto merged
mysql-test/t/fulltext.test:
  Auto merged
mysql-test/t/fulltext_order_by.test:
  Auto merged
mysql-test/t/innodb.test:
  Auto merged
mysql-test/t/join_nested.test:
  Auto merged
mysql-test/t/subselect.test:
  Auto merged
sql/item.cc:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sp.cc:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_delete.cc:
  Auto merged
sql/sql_lex.cc:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_update.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged
sql/table.h:
  Auto merged
tests/mysql_client_test.c:
  Auto merged
sql/sql_insert.cc:
  merge WL#2486
sql/sql_show.cc:
  merge WL#2486

sql/sql_class.h

@@ -1225,6 +1225,12 @@ public:
   ulonglong  limit_found_rows;
   ha_rows    cuted_fields,
              sent_row_count, examined_row_count;
+  /*
+    The set of those tables whose fields are referenced in all subqueries
+    of the query.
+    TODO: possibly this it is incorrect to have used tables in THD because
+    with more than one subquery, it is not clear what does the field mean.
+  */
   table_map  used_tables;
   USER_CONN *user_connect;
   CHARSET_INFO *db_charset;