MySQL 5.7 performance_ schema Library and sys Library commonly used SQL
Performance_ schema libraries commonly used SQL:
View tables that do not have primary keys:
SELECT DISTINCT t.table_schema, t.table_name
FROM information_schema.tables AS t
LEFT JOIN information_schema.columns AS c ON t.table_schema = c.table_schema
AND t.table_name = c.table_name AND c.column_key = "PRI"
WHERE t.table_schema NOT IN ('information_schema',' mysql', 'performance_schema')
AND c.table_name IS NULL AND t.table_type! = 'VIEW'
For example:
Mysql > SELECT DISTINCT t.table_schema, t.table_name
-> FROM information_schema.tables AS t
-> LEFT JOIN information_schema.columns AS c ON t.table_schema = c.table_schema
AND t.table_name = c.table_name AND c.column_key = "PRI"
-> WHERE t.table_schema NOT IN ('information_schema',' mysql', 'performance_schema')
-> AND c.table_name IS NULL AND t.table_type! = 'VIEW'
+-- +
| | table_schema | table_name |
+-- +
| | S85 | dsf |
| | test | innodb_lock_monitor |
| | test | innodb_monitor |
| | test | innodb_table_monitor |
| | test | innodb_tablespace_monitor |
| | zhwp102 | t_orgpriority |
| | zhwp102 | t_task_ext |
| | zhwp102 | t_web_common |
| | zhwp111 | t_orgpriority |
| | zhwp111 | t_task_ext |
| | zhwp111 | t_web_common |
| | zhwp111 | t_weibo |
| | zhwp_prod | t_orgpriority |
| | zhwp_prod | t_task_ext |
| | zhwp_prod | t_web_common |
| | zhwp_prod | t_weibo |
| | zhwpzj111 | t_orgpriority |
| | zhwpzj111 | t_task_ext |
| | zhwpzj111 | t_web_common |
| | zhwpzj111 | t_weibo |
+-- +
20 rows in set (1 min 27.55 sec)
No primary key:
Mysql > desc S85.dsf
+-- +
| | Field | Type | Null | Key | Default | Extra | |
+-- +
| | sourceDay | date | YES | | NULL |
| | sourceTime | datetime | NO | | CURRENT_TIMESTAMP |
| | affections | smallint (5) unsigned | NO | | 1 | |
+-- +
3 rows in set (0.00 sec)
See who created the temporary table
SELECT user, host, event_name, count_star AS cnt, sum_created_tmp_disk_tables AS tmp_disk_tables
Sum_created_tmp_tables AS tmp_tables
FROM performance_schema.events_statements_summary_by_account_by_event_name
WHERE sum_created_tmp_disk_tables > 0
OR sum_created_tmp_tables > 0
Users who do not properly close the database connection
SELECT ess.user, ess.host
, (a.total_connections-a.current_connections)-ess.count_star as not_closed
, (a.total_connections-a.current_connections)-ess.count_star) * 100 /
(a.total_connections-a.current_connections) as pct_not_closed
FROM performance_schema.events_statements_summary_by_account_by_event_name ess
JOIN performance_schema.accounts an on (ess.user = a.user and ess.host = a.host)
WHERE ess.event_name = 'statement/com/quit'
AND (a.total_connections-a.current_connections) > ess.count_star
DDL metadata lock tracking
1. Turn on tracking:
UPDATE performance_schema.setup_instruments SET ENABLED = 'YES' WHERE
NAME = 'wait/lock/metadata/sql/mdl'
UPDATE performance_schema.setup_consumers SET ENABLED = 'YES' WHERE
NAME = 'global_instrumentation'
two。 Query metadata lock:
Select * from performance_schema.metadata_locks
Select * from performance_schema.metadata_locks where LOCK_STATUS like 'PENDING%'
Select ID from information_schema.processlist where Info like'% 20190416%'\ G
SELECT OBJECT_TYPE,OBJECT_SCHEMA,OBJECT_NAME,LOCK_STATUS,processlist_id
FROM performance_schema.metadata_locks mdl
INNER JOIN performance_schema.threads thd ON mdl.owner_thread_id = thd.thread_id
WHERE processlist_id @ @ pseudo_thread_id
3. Turn off tracking:
UPDATE performance_schema.setup_instruments SET ENABLED = 'NO' WHERE
NAME = 'wait/lock/metadata/sql/mdl'
DDL execution progress tracking
1. Turn on tracking:
UPDATE performance_schema.setup_instruments SET ENABLED = 'YES' WHERE NAME LIKE' stage/innodb/alter%'
UPDATE performance_schema.setup_consumers SET ENABLED = 'YES' WHERE NAME LIKE'% stages%'
two。 Check the progress of DDL execution:
SELECT EVENT_NAME, WORK_COMPLETED, WORK_ESTIMATED, (WORK_COMPLETED/WORK_ESTIMATED) * 100
As COMPLETED FROM performance_schema.events_stages_current
Common SQL for sys libraries:
View table visits
Select table_schema,table_name,sum (io_read_requests+io_write_requests) io from sys.schema_table_statistics
Group by table_schema,table_name order by io desc limit 10
Check the database connection
Select * from sys.processlist\ G
Select * from sys.session limit 10\ G
Select * from sys.x$processlist\ G
Select * from sys.x$session\ G
View redundant indexes
Select table_schema,table_name,redundant_index_name,redundant_index_columns,dominant_index_name
Dominant_index_columns from sys.schema_redundant_indexes
View unused indexes
Select * from sys.schema_unused_indexes
Table self-adding ID monitoring
Select * from sys.schema_auto_increment_columns limit 10
View the files that actually consume disk IO
Select file,avg_read+avg_write as avg_io from sys.io_global_by_file_by_bytes order by avg_io desc limit 10
