SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
CREATE TABLE test.t_before(a INT);
INSERT INTO test.t_before VALUES (1);
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
test t_before
RENAME TABLE test.t_before TO test.t_after;
SELECT COUNT(*) FROM test.t_after;
COUNT(*) 1
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
test t_after
DROP TABLE test.t_after;
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
CREATE TABLE test.t1(a INT);
INSERT INTO test.t1 VALUES (1);
CREATE VIEW test.v1 AS SELECT * FROM test.t1;
SELECT COUNT(*) FROM test.v1;
COUNT(*) 1
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
test t1
DROP VIEW test.v1;
DROP TABLE test.t1;
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
SELECT EVENT_ID FROM performance_schema.events_waits_current
WHERE THREAD_ID IN
(SELECT THREAD_ID FROM performance_schema.threads) AND EVENT_NAME IN
(SELECT NAME FROM performance_schema.setup_instruments
WHERE NAME LIKE "wait/synch/%")
LIMIT 1;
create table test.t1(a int) engine=performance_schema; ERROR HY000: Can't create table `test`.`t1` (errno: 131 "Command not supported by the engine")
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
create table test.t1 like performance_schema.events_waits_current; ERROR HY000: Can't create table `test`.`t1` (errno: 131 "Command not supported by the engine")
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
create table performance_schema.t1(a int); ERROR42000: CREATE command denied to user 'root'@'localhost' for table `performance_schema`.`t1`
SELECT object_schema, object_name FROM performance_schema.objects_summary_global_by_type
WHERE object_schema='test';
object_schema object_name
drop table if exists test.ghost;
create table test.ghost (a int, b int);
alter table test.ghost add index index_a(a);
alter table test.ghost add index index_b(b);
insert into test.ghost values (1, 3);
insert into test.ghost values (2, 4);
select * from test.ghost;
a b 13 24
drop table test.ghost;
select * from performance_schema.file_instances
where file_name like "%ghost%";
FILE_NAME EVENT_NAME OPEN_COUNT
select * from performance_schema.no_such_table; ERROR42S02: Table 'performance_schema.no_such_table' doesn't exist
DROP TABLE IF EXISTS t_60905;
CREATE TABLE t_60905 (i INT, j INT, KEY(i)) ENGINE = InnoDB;
INSERT INTO t_60905 VALUES
(1,2), (3,4), (5,6), (7,8), (9,10);
DELETE FROM t_60905 WHERE i = 1;
DELETE FROM t_60905 WHERE j = 8;
SELECT object_schema,
object_name,
index_name,
count_fetch,
count_insert,
count_update,
count_delete
FROM performance_schema.table_io_waits_summary_by_index_usage
WHERE object_schema = 'test' AND object_name = 't_60905';
object_schema object_name index_name count_fetch count_insert count_update count_delete
test t_60905 i 2001
test t_60905 NULL 5501
DROP TABLE t_60905;
show global variables like "performance_schema_max_thread_instances";
Variable_name Value
performance_schema_max_thread_instances 400
explain select * from performance_schema.threads;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE threads ALL NULL NULL NULL NULL 256
use performance_schema;
show events;
Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation
show events from performance_schema;
Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation
show events where Db= 'performance_schema';
Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation
use test;
use test;
truncate performance_schema.events_statements_history;
truncate performance_schema.events_statements_history_long;
select * from t1; ERROR42S02: Table 'test.t1' doesn't exist
select mysql_errno, returned_sqlstate, message_text, errors, warnings
from performance_schema.events_statements_history where errors > 0;
mysql_errno returned_sqlstate message_text errors warnings 114642S02 Table 'test.t1' doesn't exist 1 0
#
select mysql_errno, returned_sqlstate, message_text, errors, warnings from
performance_schema.events_statements_history_long where errors > 0;
mysql_errno returned_sqlstate message_text errors warnings 114642S02 Table 'test.t1' doesn't exist 1 0
use performance_schema;
truncate performance_schema.events_statements_history;
select 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' AS A;
A
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
select _utf8mb4 'ваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑваÑÑ' as B;
B
вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�вас�
select count(*) from events_statements_history where sql_text like "%...";
count(*) 2
use test;
create table t1 (id int);
insert into t1 values (1), (2), (3);
truncate performance_schema.events_statements_history;
select * from t1;
id 1 2 3
insert into t1 select RAND()*10000 from t1;
select sql_text, rows_examined from performance_schema.events_statements_history;
sql_text rows_examined
truncate performance_schema.events_statements_history 0
select * from t1 3
insert into t1 select RAND()*10000 from t1 6
drop table t1;
#
# MDEV-17896 Assertion `pfs->get_refcount() > 0' failed
# in release_table_share
#
SELECT COUNT(*)<@@performance_schema_max_table_instances FROM
performance_schema.objects_summary_global_by_type WHERE OBJECT_TYPE='TABLE';
COUNT(*)<@@performance_schema_max_table_instances 1
CREATE TABLE t0(a INT);
SELECT * FROM t0;
a
DROP TEMPORARY TABLE IF EXISTS t0;
Warnings:
Note 1051 Unknown table 'test.t0'
FLUSH TABLE t0;
DROP TABLE t0;
#
# MDEV-24364 Alter rename table does not remove PFS share
#
create orreplace table yt4 (x int) engine innodb;
alter table yt4 rename to t1, algorithm=copy;
drop tables t1;
select object_type, object_schema, object_name
from performance_schema.objects_summary_global_by_type
where object_schema="test";
object_type object_schema object_name
#
# MDEV-28344: sys.ps_setup_save and dependent procedures fail
# with ER_ILLEGAL_HA_CREATE_OPTION
#
CREATE TEMPORARY TABLE t1 (t int) ENGINE = PERFORMANCE_SCHEMA; ERROR HY000: Table storage engine 'PERFORMANCE_SCHEMA' does not support the create option 'TEMPORARY'
CREATE TEMPORARY TABLE t1 LIKE performance_schema.setup_actors; ERROR HY000: Table storage engine 'PERFORMANCE_SCHEMA' does not support the create option 'TEMPORARY' SET @default_storage_engine_old = @@default_storage_engine; SET default_storage_engine = performance_schema;
CREATE TEMPORARY TABLE t1 (t int); ERROR HY000: Table storage engine 'PERFORMANCE_SCHEMA' does not support the create option 'TEMPORARY' SET @@default_storage_engine = @default_storage_engine_old;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.13 Sekunden
(vorverarbeitet am 2026-10-08)
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