Backport of:

----------------------------------------------------------
revno: 2630.10.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-lock-tables-tidyup
timestamp: Wed 2008-06-11 15:49:58 +0400
message:
  WL#3726, review fixes.
  Now that we have metadata locks, we don't need to keep a crippled
  TABLE instance in the table cache to indicate that a table is locked.
  Remove all code that used this technique. Instead, rely on metadata
  locks and use the standard open_table() and close_thread_table()
  to manipulate with the table cache tables.
  Removes a list of functions that have become unused (see the comment
  for sql_base.cc for details).
  Under LOCK TABLES, keep a TABLE_LIST instance for each table
  that may be temporarily closed. For that, implement an own class for
  LOCK TABLES mode, Locked_tables_list.

This is a pre-requisite patch for WL#4144.
This is not exactly a backport: there is no new 
online ALTER table in Celosia, so the old alter table
code was changed to work with the new table cache API.


mysql-test/r/lock.result:
  Update results (WL#3726 post-review patch).
mysql-test/r/trigger-compat.result:
  We take the table from the table cache now, thus no warning.
mysql-test/suite/rpl/r/rpl_trigger.result:
  We take the table from the table cache now, thus no warning.
mysql-test/t/lock.test:
  Additional tests for LOCK TABLES mode (previously not covered by
  the test suite (WL#3726).
sql/field.h:
  Remove reopen_table().
sql/lock.cc:
  Remove an obsolete parameter of mysql_lock_remove().
  It's not used anywhere now either.
sql/mysql_priv.h:
  Add 4 new open_table() flags.
  Remove declarations of removed functions.
sql/sp_head.cc:
  Rename thd->mdl_el_root to thd->locked_tables_root.
sql/sql_acl.cc:
  Use the new implementation of unlock_locked_tables().
sql/sql_base.cc:
  Implement class Locked_tables_list.
  Implement close_all_tables_for_name().
  Rewrite close_cached_tables() to use the new reopen_tables().
  Remove reopen_table(), reopen_tables(), reopen_table_entry() 
  (ex. open_unireg_entry()), close_data_files_and_leave_as_placeholders(),
  close_handle_and_leave_table_as_placeholder(), close_cached_table(),
  table_def_change_share(), reattach_merge(), reopen_name_locked_table(),
  unlink_open_table().
  
  Move acquisition of a metadata lock into an own function
  - open_table_get_mdl_lock().
sql/sql_class.cc:
  Deploy class Locked_tables_list.
sql/sql_class.h:
  Declare class Locked_tables_list.
  Keep one instance of this class in class THD.
  Rename mdl_el_root to locked_tables_root.
sql/sql_db.cc:
  Update a comment.
sql/sql_insert.cc:
  Use the plain open_table() to open a just created table in
  CREATE TABLE .. SELECT.
sql/sql_parse.cc:
  Use thd->locked_tables_list to enter and leave LTM_LOCK_TABLES mode.
sql/sql_partition.cc:
  Deploy the new method of working with partitioned table locks.
sql/sql_servers.cc:
  Update to the new signature of unlock_locked_tables().
sql/sql_table.cc:
  In mysql_rm_table_part2(), the branch that removes a table under
  LOCK TABLES, make sure that the table being dropped
  is also removed from THD::locked_tables_list.
  Update ALTER TABLE and CREATE TABLE LIKE implementation to use
  open_table() and close_all_tables_for_name() instead of 
  reopen_tables().
sql/sql_trigger.cc:
  Use the new locking way.
sql/table.h:
  Add TABLE::pos_in_locked_tables, which is used only under
  LOCK TABLES.

1 files changed, 2 insertions, 2 deletions

diff --git a/sql/sql_db.cc b/sql/sql_db.cc
index b5c51601faf..1b61a96d7ff 100644
--- a/sql/sql_db.cc
+++ b/sql/sql_db.cc
@@ -1956,8 +1956,8 @@ bool mysql_upgrade_db(THD *thd, LEX_STRING *old_db)
 
   /*
     Step7: drop the old database.
-    remove_db_from_cache(olddb) and query_cache_invalidate(olddb)
-    are done inside mysql_rm_db(), no needs to execute them again.
+    query_cache_invalidate(olddb) is done inside mysql_rm_db(), no need
+    to execute them again.
     mysql_rm_db() also "unuses" if we drop the current database.
   */
   error= mysql_rm_db(thd, old_db->str, 0, 1);