select * from performance_schema.table_lock_waits_summary_by_table
limit 1;
select * from performance_schema.table_lock_waits_summary_by_table
where object_name='FOO';
insert into performance_schema.table_lock_waits_summary_by_table
set object_type='TABLE', object_name='FOO', object_schema='BAR',
count_star=1, sum_timer_wait=2, min_timer_wait=3,
avg_timer_wait=4, max_timer_wait=5;
ERROR 42000: INSERT command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
update performance_schema.table_lock_waits_summary_by_table
set count_star=12;
ERROR 42000: UPDATE command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
update performance_schema.table_lock_waits_summary_by_table
set count_star=12 where object_name like "FOO";
ERROR 42000: UPDATE command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
delete from performance_schema.table_lock_waits_summary_by_table
where count_star=1;
ERROR 42000: DELETE command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
delete from performance_schema.table_lock_waits_summary_by_table;
ERROR 42000: DELETE command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
LOCK TABLES performance_schema.table_lock_waits_summary_by_table READ;
ERROR 42000: SELECT, LOCK TABLES command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
UNLOCK TABLES;
LOCK TABLES performance_schema.table_lock_waits_summary_by_table WRITE;
ERROR 42000: SELECT, LOCK TABLES command denied to user 'root'@'localhost' for table `performance_schema`.`table_lock_waits_summary_by_table`
UNLOCK TABLES;
#
# MDEV-25325 column_comment for performance_schema tables
#
select column_name, column_comment 
from information_schema.columns 
where table_schema='performance_schema' and table_name='table_lock_waits_summary_by_table';
column_name	column_comment
OBJECT_TYPE	Since this table records waits by table, always set to TABLE.
OBJECT_SCHEMA	Schema name.
OBJECT_NAME	Table name.
COUNT_STAR	Number of summarized events and the sum of the x_READ and x_WRITE columns.
SUM_TIMER_WAIT	Total wait time of the summarized events that are timed.
MIN_TIMER_WAIT	Minimum wait time of the summarized events that are timed.
AVG_TIMER_WAIT	Average wait time of the summarized events that are timed.
MAX_TIMER_WAIT	Maximum wait time of the summarized events that are timed.
COUNT_READ	Number of all read operations, and the sum of the equivalent x_READ_NORMAL, x_READ_WITH_SHARED_LOCKS, x_READ_HIGH_PRIORITY and x_READ_NO_INSERT columns.
SUM_TIMER_READ	Total wait time of all read operations that are timed.
MIN_TIMER_READ	Minimum wait time of all read operations that are timed.
AVG_TIMER_READ	Average wait time of all read operations that are timed.
MAX_TIMER_READ	Maximum wait time of all read operations that are timed.
COUNT_WRITE	Number of all write operations, and the sum of the equivalent x_WRITE_ALLOW_WRITE, x_WRITE_CONCURRENT_INSERT, x_WRITE_DELAYED, x_WRITE_LOW_PRIORITY and x_WRITE_NORMAL columns.
SUM_TIMER_WRITE	Total wait time of all write operations that are timed.
MIN_TIMER_WRITE	Minimum wait time of all write operations that are timed.
AVG_TIMER_WRITE	Average wait time of all write operations that are timed.
MAX_TIMER_WRITE	Maximum wait time of all write operations that are timed.
COUNT_READ_NORMAL	Number of all internal read normal locks.
SUM_TIMER_READ_NORMAL	Total wait time of all internal read normal locks that are timed.
MIN_TIMER_READ_NORMAL	Minimum wait time of all internal read normal locks that are timed.
AVG_TIMER_READ_NORMAL	Average wait time of all internal read normal locks that are timed.
MAX_TIMER_READ_NORMAL	Maximum wait time of all internal read normal locks that are timed.
COUNT_READ_WITH_SHARED_LOCKS	Number of all internal read with shared locks.
SUM_TIMER_READ_WITH_SHARED_LOCKS	Total wait time of all internal read with shared locks that are timed.
MIN_TIMER_READ_WITH_SHARED_LOCKS	Minimum wait time of all internal read with shared locks that are timed.
AVG_TIMER_READ_WITH_SHARED_LOCKS	Average wait time of all internal read with shared locks that are timed.
MAX_TIMER_READ_WITH_SHARED_LOCKS	Maximum wait time of all internal read with shared locks that are timed.
COUNT_READ_HIGH_PRIORITY	Number of all internal read high priority locks.
SUM_TIMER_READ_HIGH_PRIORITY	Total wait time of all internal read high priority locks that are timed.
MIN_TIMER_READ_HIGH_PRIORITY	Minimum wait time of all internal read high priority locks that are timed.
AVG_TIMER_READ_HIGH_PRIORITY	Average wait time of all internal read high priority locks that are timed.
MAX_TIMER_READ_HIGH_PRIORITY	Maximum wait time of all internal read high priority locks that are timed.
COUNT_READ_NO_INSERT	Number of all internal read no insert locks.
SUM_TIMER_READ_NO_INSERT	Total wait time of all internal read no insert locks that are timed.
MIN_TIMER_READ_NO_INSERT	Minimum wait time of all internal read no insert locks that are timed.
AVG_TIMER_READ_NO_INSERT	Average wait time of all internal read no insert locks that are timed.
MAX_TIMER_READ_NO_INSERT	Maximum wait time of all internal read no insert locks that are timed.
COUNT_READ_EXTERNAL	Number of all external read locks.
SUM_TIMER_READ_EXTERNAL	Total wait time of all external read locks that are timed.
MIN_TIMER_READ_EXTERNAL	Minimum wait time of all external read locks that are timed.
AVG_TIMER_READ_EXTERNAL	Average wait time of all external read locks that are timed.
MAX_TIMER_READ_EXTERNAL	Maximum wait time of all external read locks that are timed.
COUNT_WRITE_ALLOW_WRITE	Number of all internal read normal locks.
SUM_TIMER_WRITE_ALLOW_WRITE	Total wait time of all internal write allow write locks that are timed.
MIN_TIMER_WRITE_ALLOW_WRITE	Minimum wait time of all internal write allow write locks that are timed.
AVG_TIMER_WRITE_ALLOW_WRITE	Average wait time of all internal write allow write locks that are timed.
MAX_TIMER_WRITE_ALLOW_WRITE	Maximum wait time of all internal write allow write locks that are timed.
COUNT_WRITE_CONCURRENT_INSERT	Number of all internal concurrent insert write locks.
SUM_TIMER_WRITE_CONCURRENT_INSERT	Total wait time of all internal concurrent insert write locks that are timed.
MIN_TIMER_WRITE_CONCURRENT_INSERT	Minimum wait time of all internal concurrent insert write locks that are timed.
AVG_TIMER_WRITE_CONCURRENT_INSERT	Average wait time of all internal concurrent insert write locks that are timed.
MAX_TIMER_WRITE_CONCURRENT_INSERT	Maximum wait time of all internal concurrent insert write locks that are timed.
COUNT_WRITE_DELAYED	Number of all internal write delayed locks.
SUM_TIMER_WRITE_DELAYED	Total wait time of all internal write delayed locks that are timed.
MIN_TIMER_WRITE_DELAYED	Minimum wait time of all internal write delayed locks that are timed.
AVG_TIMER_WRITE_DELAYED	Average wait time of all internal write delayed locks that are timed.
MAX_TIMER_WRITE_DELAYED	Maximum wait time of all internal write delayed locks that are timed.
COUNT_WRITE_LOW_PRIORITY	Number of all internal write low priority locks.
SUM_TIMER_WRITE_LOW_PRIORITY	Total wait time of all internal write low priority locks that are timed.
MIN_TIMER_WRITE_LOW_PRIORITY	Minimum wait time of all internal write low priority locks that are timed.
AVG_TIMER_WRITE_LOW_PRIORITY	Average wait time of all internal write low priority locks that are timed.
MAX_TIMER_WRITE_LOW_PRIORITY	Maximum wait time of all internal write low priority locks that are timed.
COUNT_WRITE_NORMAL	Number of all internal write normal locks.
SUM_TIMER_WRITE_NORMAL	Total wait time of all internal write normal locks that are timed.
MIN_TIMER_WRITE_NORMAL	Minimum wait time of all internal write normal locks that are timed.
AVG_TIMER_WRITE_NORMAL	Average wait time of all internal write normal locks that are timed.
MAX_TIMER_WRITE_NORMAL	Maximum wait time of all internal write normal locks that are timed.
COUNT_WRITE_EXTERNAL	Number of all external write locks.
SUM_TIMER_WRITE_EXTERNAL	Total wait time of all external write locks that are timed.
MIN_TIMER_WRITE_EXTERNAL	Minimum wait time of all external write locks that are timed.
AVG_TIMER_WRITE_EXTERNAL	Average wait time of all external write locks that are timed.
MAX_TIMER_WRITE_EXTERNAL	Maximum wait time of all external write locks that are timed.
