Commit f3a56a17 authored by unknown's avatar unknown
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SHOW STATUS does not anymore change local status variables (except... 

SHOW STATUS does not anymore change local status variables (except com_show_status). Global status variables are still updated.
SHOW STATUS are not anymore put in slow query log because of no index usage.

Implemntation done by removing orig_sql_command and moving logic of SHOW STATUS to mysql_excute_command()
This simplifies code and allows us to remove some if statements all over the code.

Upgraded uc_update_queries[] to sql_command_flags and added more bitmaps to better categorize commands.
This allowed some overall simplifaction when testing sql_command.

Fixes bugs:
Bug#10210: running SHOW STATUS increments counters it shouldn't
Bug#19764: SHOW commands end up in the slow log as table scans


mysql-test/r/grant_cache.result:
  Fixed results after SHOW STATUS doesn't anymore affect status variables
mysql-test/r/information_schema.result:
  Added extra test to cover more code
mysql-test/r/query_cache.result:
  Remove resuts from previous tests
mysql-test/r/status.result:
  Added more tests for testing of last_query_cost and how SHOW STATUS affects status variables.
  (Bug#10210)
mysql-test/r/temp_table.result:
  Fixed results after SHOW STATUS doesn't anymore affect status variables
mysql-test/r/union.result:
  Fixed results after SHOW STATUS is not logged to slow query log
  (Bug#19764)
mysql-test/t/events_microsec.test:
  Disable warnings at init
mysql-test/t/information_schema.test:
  Added extra test to cover more code
mysql-test/t/query_cache.test:
  Remove resuts from previous tests
mysql-test/t/status.test:
  Added more tests for testing of last_query_cost and how SHOW STATUS affects status variables.
  (Bug #10210)
sql/mysql_priv.h:
  Added 'sql_command_flags'
sql/sql_class.cc:
  New function add_diff_to_status(), used to update global status variables when using SHOW STATUS
sql/sql_class.h:
  New function 'fill_information_schema_tables()'
  (One could not anymore use fill_derived_tables() for this as only_view_structures() is not relevant for information schema tables)
  Added defines for bit flags in sql_command_flags[]
sql/sql_lex.cc:
  Remove orig_sql_command
sql/sql_lex.h:
  Remove orig_sql_command
sql/sql_parse.cc:
  Rename uc_update_queries -> sql_command_flags.
  Enhanced 'sql_command_flags' to better classify SQL commands
  uc_update_queries[] != 0 is changed to (sql_command_flags[] & CF_CHANGES_DATA)
  lex->orig_sql_command == SQLCOM_END is changed to (sql_command_flags[lex->sql_command] & CF_STATUS_COMMAND) == 0)
  
  Simplify incrementing of thd->status_var.com_stat[] as we don't have to do special handling for SHOW commands.
  
  Split SQLCOM_SELECT handling in mysql_execute_command() to a separate function.
  Added special handling of SHOW STATUS commands in mysql_execute_command() and call common SQLCOM_SELECT handling.
  These changes allows us to easily fix that we save and restore status variables during execution of a SHOW STATUS command.
  Don't log SHOW STATUS commands to slow query log.
  
  This fixes Bug#10210 and Bug#19764 without adding additional 'if' code.
  (The new code is faster than the original as we now have fewer if's than before)
sql/sql_prepare.cc:
  Clean up prepare-check handling of SQLCOM commands by using sql_command_flags[]
  This simplifes code and ensures that code works even if someone forgets to put a new status commands into the switch statement.
sql/sql_select.cc:
  Remove special handling of SHOW STATUS.
  (This is now done in SQLCOM_SHOW_STATUS part in mysql_execute_command())
sql/sql_show.cc:
  Remove orig_sql_command
  Only change sql_command during 'open_normal_and_derived_tables()' (for views) and not for the full duration of generating data.
  Changed 'show status' to use thd->initial_status_var to ensure that the current statement is not affecting the to-be-used values.
  Use thd->fill_information_schema_tables() instead of 'thd->fill_derived_tables()' as the later wrongly checks the value of sql_command.
sql/sql_yacc.yy:
  Remove usage of orig_sql_command.
  One side effect of this is that we need to test for cursors if the current command is a SELECT or a SHOW command.
sql/structs.h:
  Updated comment
parent cd3fa2ee

mysql-test/r/grant_cache.result

+8 −8
Original line number Diff line number Diff line
@@ -60,7 +60,7 @@ Variable_name Value 
Qcache_hits	0

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	5

Qcache_not_cached	0

select "user1";

user1

user1
@@ -72,7 +72,7 @@ Variable_name Value 
Qcache_hits	0

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	9

Qcache_not_cached	1

select * from t1;

a	b	c

1	1	1
@@ -85,7 +85,7 @@ Variable_name Value 
Qcache_hits	1

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	12

Qcache_not_cached	1

select a from t1 ;

a

1
@@ -98,7 +98,7 @@ Variable_name Value 
Qcache_hits	2

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	15

Qcache_not_cached	1

select c from t1;

c

1
@@ -111,7 +111,7 @@ Variable_name Value 
Qcache_hits	3

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	18

Qcache_not_cached	1

show grants for current_user();

Grants for @localhost

GRANT USAGE ON *.* TO ''@'localhost'
@@ -144,7 +144,7 @@ Variable_name Value 
Qcache_hits	7

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	22

Qcache_not_cached	2

select "user3";

user3

user3
@@ -168,7 +168,7 @@ Variable_name Value 
Qcache_hits	7

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	30

Qcache_not_cached	7

select "user4";

user4

user4
@@ -198,7 +198,7 @@ Variable_name Value 
Qcache_hits	8

show status like "Qcache_not_cached";

Variable_name	Value

Qcache_not_cached	34

Qcache_not_cached	8

set names binary;

delete from mysql.user where user in ("mysqltest_1","mysqltest_2","mysqltest_3");

delete from mysql.db where user in ("mysqltest_1","mysqltest_2","mysqltest_3");

mysql-test/r/information_schema.result

+2 −0
Original line number Diff line number Diff line
@@ -199,6 +199,8 @@ select table_name, column_name, privileges from information_schema.columns 
where table_schema = 'mysqltest' and table_name = 'v1';

table_name	column_name	privileges

v1	c	select

explain select * from v1;

ERROR HY000: EXPLAIN/SHOW can not be issued; lacking privileges for underlying table

drop view v1, mysqltest.v1;

drop tables mysqltest.t4, mysqltest.t1, t2, t3, t5;

drop database mysqltest;

mysql-test/r/query_cache.result

+1 −0
Original line number Diff line number Diff line
@@ -1050,6 +1050,7 @@ Qcache_hits 1 
drop table t1;

create table t1 (a int);

insert into t1 values (1),(2);

drop procedure if exists p1;

CREATE PROCEDURE `p1`()

begin

Declare c1 cursor for select a from t1;

mysql-test/r/status.result

+50 −0
Original line number Diff line number Diff line
@@ -23,6 +23,32 @@ select 1; 
show status like 'last_query_cost';

Variable_name	Value

Last_query_cost	0.000000

create table t1 (a int);

insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);

insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);

insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);

insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);

insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);

select * from t1 where a=6;

a

6

6

6

6

6

show status like 'last_query_cost';

Variable_name	Value

Last_query_cost	12.084449

show status like 'last_query_cost';

Variable_name	Value

Last_query_cost	12.084449

select 1;

1

1

show status like 'last_query_cost';

Variable_name	Value

Last_query_cost	0.000000

drop table t1;

FLUSH STATUS;

SHOW STATUS LIKE 'max_used_connections';

Variable_name	Value
@@ -43,3 +69,27 @@ SHOW STATUS LIKE 'max_used_connections'; 
Variable_name	Value

Max_used_connections	5

SET GLOBAL thread_cache_size=@save_thread_cache_size;

show status like 'com_show_status';

Variable_name	Value

Com_show_status	3

show status like 'hand%write%';

Variable_name	Value

Handler_write	0

show status like '%tmp%';

Variable_name	Value

Created_tmp_disk_tables	0

Created_tmp_files	0

Created_tmp_tables	0

show status like 'hand%write%';

Variable_name	Value

Handler_write	0

show status like '%tmp%';

Variable_name	Value

Created_tmp_disk_tables	0

Created_tmp_files	0

Created_tmp_tables	0

show status like 'com_show_status';

Variable_name	Value

Com_show_status	8

rnd_diff	tmp_table_diff

20	8

mysql-test/r/temp_table.result

+1 −1
Original line number Diff line number Diff line
@@ -98,7 +98,7 @@ d 
show status like "created_tmp%tables";

Variable_name	Value

Created_tmp_disk_tables	0

Created_tmp_tables	2

Created_tmp_tables	1

drop table t1;

create temporary table v1 as select 'This is temp. table' A;

create view v1 as select 'This is view' A;