Statement Summary Tables

The statement summary tables aggregate information about statement waits:

events_statements_summary_by_thread_by_event_name: Statement events summarized per thread and event name
events_statements_summary_global_by_event_name: Statement events summarized per event name

For example:

mysql> SELECT * FROM events_statements_summary_global_by_event_name\G
*************************** 1. row ***************************
 EVENT_NAME: statement/sql/select
 COUNT_STAR: 25
 SUM_TIMER_WAIT: 1535983999000
 MIN_TIMER_WAIT: 209823000
 AVG_TIMER_WAIT: 61439359000
 MAX_TIMER_WAIT: 1363397650000
 SUM_LOCK_TIME: 20186000000
 SUM_ERRORS: 0
 SUM_WARNINGS: 0
 SUM_ROWS_AFFECTED: 0
 SUM_ROWS_SENT: 388
 SUM_ROWS_EXAMINED: 370
SUM_CREATED_TMP_DISK_TABLES: 0
 SUM_CREATED_TMP_TABLES: 0
 SUM_SELECT_FULL_JOIN: 0
 SUM_SELECT_FULL_RANGE_JOIN: 0
 SUM_SELECT_RANGE: 0
 SUM_SELECT_RANGE_CHECK: 0
 SUM_SELECT_SCAN: 6
 SUM_SORT_MERGE_PASSES: 0
 SUM_SORT_RANGE: 0
 SUM_SORT_ROWS: 0
 SUM_SORT_SCAN: 0
 SUM_NO_INDEX_USED: 6
 SUM_NO_GOOD_INDEX_USED: 0
...

TRUNCATE TABLE is permitted for summary tables. It resets the counters to zero rather than removing rows.

The statement summary tables have these grouping columns to indicate how events are aggregated:

events_statements_summary_global_by_event_name has an EVENT_NAME column. Each row summarizes events for a given instrument.
events_statements_summary_by_thread_by_event_name has THREAD_ID and EVENT_NAME columns. Each row summarizes events for a given thread instrument instance.

The statement summary tables have these summary columns containing aggregated values:

COUNT_STAR, SUM_TIMER_WAIT, MIN_TIMER_WAIT, AVG_TIMER_WAIT MAX_TIMER_WAIT
These columns are analogous to the columns of the same names in the events_waits_summary_global_by_event_name and events_waits_summary_by_thread_by_event_name tables, except that the statement summary tables aggregate waits from events-statements-current rather than events_waits_current.
SUM_xxx
The aggregate of the corresponding xxx column in the events_statements_current table. For example, the SUM_LOCK_TIME and SUM_ERRORS columns in statement summary tables are the aggregates of the LOCK_TIME and ERRORS columns in events_statements_current table.

These tables were added in MariaDB 5.6.3.

Statement Summary Tables

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