select * from performance_schema.file_summary_by_event_name
where event_name like 'Wait/io/%' limit 1;
select * from performance_schema.file_summary_by_event_name
where event_name='FOO';
insert into performance_schema.file_summary_by_event_name
set event_name='FOO', count_read=1, count_write=2,
sum_number_of_bytes_read=4, sum_number_of_bytes_write=5;
ERROR 42000: INSERT command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
update performance_schema.file_summary_by_event_name
set count_read=12;
ERROR 42000: UPDATE command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
update performance_schema.file_summary_by_event_name
set count_write=12 where event_name like "FOO";
ERROR 42000: UPDATE command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
delete from performance_schema.file_summary_by_event_name
where count_read=1;
ERROR 42000: DELETE command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
delete from performance_schema.file_summary_by_event_name;
ERROR 42000: DELETE command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
LOCK TABLES performance_schema.file_summary_by_event_name READ;
ERROR 42000: SELECT, LOCK TABLES command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
UNLOCK TABLES;
LOCK TABLES performance_schema.file_summary_by_event_name WRITE;
ERROR 42000: SELECT, LOCK TABLES command denied to user 'root'@'localhost' for table `performance_schema`.`file_summary_by_event_name`
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='file_summary_by_event_name';
column_name	column_comment
EVENT_NAME	Event name.
COUNT_STAR	Number of summarized events
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, including FGETS, FGETC, FREAD, and READ.
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.
SUM_NUMBER_OF_BYTES_READ	Bytes read by read operations.
COUNT_WRITE	Number of all write operations, including FPUTS, FPUTC, FPRINTF, VFPRINTF, FWRITE, and PWRITE.
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.
SUM_NUMBER_OF_BYTES_WRITE	Bytes written by write operations.
COUNT_MISC	Number of all miscellaneous operations not counted above, including CREATE, DELETE, OPEN, CLOSE, STREAM_OPEN, STREAM_CLOSE, SEEK, TELL, FLUSH, STAT, FSTAT, CHSIZE, RENAME, and SYNC.
SUM_TIMER_MISC	Total wait time of all miscellaneous operations that are timed.
MIN_TIMER_MISC	Minimum wait time of all miscellaneous operations that are timed.
AVG_TIMER_MISC	Average wait time of all miscellaneous operations that are timed.
MAX_TIMER_MISC	Maximum wait time of all miscellaneous operations that are timed.
