Merge abarkov@bk-internal.mysql.com:/home/bk/mysql-5.0

into  mysql.com:/usr/home/bar/mysql-5.0

mysql-test/r/information_schema.result

@@ -979,3 +979,14 @@ WHERE TABLE_SCHEMA='test' AND TABLE_TYPE='BASE TABLE');
 Name	Engine	Version	Row_format	Rows	Avg_row_length	Data_length	Max_data_length	Index_length	Data_free	Auto_increment	Create_time	Update_time	Check_time	Collation	Checksum	Create_options	Comment
 t1	MyISAM	10	Fixed	0	0	0	#	1024	0	NULL	#	#	NULL	latin1_swedish_ci	NULL		
 t2	MyISAM	10	Fixed	0	0	0	#	1024	0	NULL	#	#	NULL	latin1_swedish_ci	NULL		
+DROP TABLE t1,t2;
+create table t1(f1 int);
+create view v1 (c) as select f1 from t1;
+select database();
+database()
+NULL
+show fields from test.v1;
+Field	Type	Null	Key	Default	Extra
+c	int(11)	YES		NULL	
+drop view v1;
+drop table t1;

mysql-test/r/variables.result

@@ -545,3 +545,10 @@ select @@max_heap_table_size > 0;
 select @@have_innodb;
 @@have_innodb
 #
+select @@character_set_system;
+@@character_set_system
+utf8
+set global character_set_system = latin1;
+ERROR HY000: Variable 'character_set_system' is a read only variable
+set @@global.version_compile_os='234';
+ERROR HY000: Variable 'version_compile_os' is a read only variable

mysql-test/t/information_schema.test

@@ -665,4 +665,16 @@ SHOW TABLE STATUS FROM test
   WHERE name IN ( SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
                     WHERE TABLE_SCHEMA='test' AND TABLE_TYPE='BASE TABLE');
 
-DROP TABLE t1,t2
+DROP TABLE t1,t2;
+
+#
+# Bug #12905 show fields from view behaving erratically with current database
+#
+create table t1(f1 int);
+create view v1 (c) as select f1 from t1;
+connect (con5,localhost,root,,*NO-ONE*);
+select database();
+show fields from test.v1;
+connection default;
+drop view v1;
+drop table t1;

mysql-test/t/variables.test

@@ -435,3 +435,12 @@ select @@max_heap_table_size > 0;
 
 --replace_column 1 #
 select @@have_innodb;
+
+#
+# Bug #11775 Variable character_set_system does not exist (sometimes)
+#
+select @@character_set_system;
+--error 1238
+set global character_set_system = latin1;
+--error 1238
+set @@global.version_compile_os='234';

sql/set_var.cc

@@ -142,10 +142,7 @@ sys_var_long_ptr	sys_binlog_cache_size("binlog_cache_size",
 sys_var_thd_ulong	sys_bulk_insert_buff_size("bulk_insert_buffer_size",
 						  &SV::bulk_insert_buff_size);
 sys_var_character_set_server	sys_character_set_server("character_set_server");
-sys_var_str			sys_charset_system("character_set_system",
-				    sys_check_charset,
-				    sys_update_charset,
-				    sys_set_default_charset,
+sys_var_const_str       sys_charset_system("character_set_system",
                                            (char *)my_charset_utf8_general_ci.name);
 sys_var_character_set_database	sys_character_set_database("character_set_database");
 sys_var_character_set_client  sys_character_set_client("character_set_client");
@@ -569,6 +566,7 @@ sys_var *sys_variables[]=
   &sys_character_set_client,
   &sys_character_set_connection,
   &sys_character_set_results,
+  &sys_charset_system,
   &sys_collation_connection,
   &sys_collation_database,
   &sys_collation_server,
@@ -1117,27 +1115,6 @@ static void sys_default_ftb_syntax(THD *thd, enum_var_type type)
 	  sizeof(ft_boolean_syntax)-1);
 }
 
-/*
-  The following 3 functions need to be changed in 4.1 when we allow
-  one to change character sets
-*/
-
-static int sys_check_charset(THD *thd, set_var *var)
-{
-  return 0;
-}
-
-
-static bool sys_update_charset(THD *thd, set_var *var)
-{
-  return 0;
-}
-
-
-static void sys_set_default_charset(THD *thd, enum_var_type type)
-{
-}
-
 
 /*
   If one sets the LOW_PRIORIY UPDATES flag, we also must change the

sql/set_var.h

@@ -190,6 +190,7 @@ class sys_var_const_str :public sys_var
     return 1;
   }
   bool check_default(enum_var_type type) { return 1; }
+  bool is_readonly() const { return 1; }
 };
 
 
@@ -900,7 +901,7 @@ int sql_set_variables(THD *thd, List<set_var_base> *var_list);
 bool not_all_support_one_shot(List<set_var_base> *var_list);
 void fix_delay_key_write(THD *thd, enum_var_type type);
 ulong fix_sql_mode(ulong sql_mode);
-extern sys_var_str sys_charset_system;
+extern sys_var_const_str sys_charset_system;
 extern sys_var_str sys_init_connect;
 extern sys_var_str sys_init_slave;
 extern sys_var_thd_time_zone sys_time_zone;

sql/sql_show.cc

@@ -1988,9 +1988,19 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
     /*
       get_all_tables() returns 1 on failure and 0 on success thus
       return only these and not the result code of ::process_table()
+
+      We should use show_table_list->alias instead of 
+      show_table_list->table_name because table_name
+      could be changed during opening of I_S tables. It's safe
+      to use alias because alias contains original table name 
+      in this case(this part of code is used only for 
+      'show columns' & 'show statistics' commands).
     */
     error= test(schema_table->process_table(thd, show_table_list,
-                                    table, res, show_table_list->db,
+                                            table, res, 
+                                            (show_table_list->view ?
+                                             show_table_list->view_db.str :
+                                             show_table_list->db),
                                             show_table_list->alias));
     close_thread_tables(thd);
     show_table_list->table= 0;
@@ -2092,6 +2102,13 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
             lex->derived_tables= 0;
             res= open_normal_and_derived_tables(thd, show_table_list,
                                                 MYSQL_LOCK_IGNORE_FLUSH);
+            /*
+              We should use show_table_list->alias instead of 
+              show_table_list->table_name because table_name
+              could be changed during opening of I_S tables. It's safe
+              to use alias because alias contains original table name 
+              in this case.
+            */
             res= schema_table->process_table(thd, show_table_list, table,
                                             res, base_name,
                                             show_table_list->alias);