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Performance Schema table_lock_waits_summary_by_table Table

MariaDB starting with 10.0

The table_lock_waits_summary_by_table table, along with many other new Performance Schema tables, was added in MariaDB 10.0.

The table_lock_waits_summary_by_table table records table lock waits by table.

Column	Description
`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.

You can TRUNCATE the table, which will reset all counters to zero.

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https://mariadb.com/kb/en/performance-schema-table_lock_waits_summary_by_table-table/