## • SOURCE 

The name of the source file containing the instrumented code that produced the event and the line number in the file at which the instrumentation occurs. This enables you to check the source to determine exactly what code is involved. 

## • TIMER_START , TIMER_END , TIMER_WAIT 

Timing information for the event. The unit for these values is picoseconds (trillionths of a second). The TIMER_START  and TIMER_END  values indicate when event timing started and ended. TIMER_WAIT  is the event elapsed time (duration). 

If an event has not finished, TIMER_END  is the current timer value and TIMER_WAIT  is the time elapsed so far ( TIMER_END − TIMER_START ). 

If an event is produced from an instrument that has TIMED = NO , timing information is not collected, and TIMER_START , TIMER_END , and TIMER_WAIT  are all NULL . 

For discussion of picoseconds as the unit for event times and factors that affect time values, see Section 27.4.1, “Performance Schema Event Timing” . 

## • ACCESS_MODE 

The transaction access mode. The value is READ WRITE  or READ ONLY . 

## • ISOLATION_LEVEL 

The transaction isolation level. The value is REPEATABLE READ , READ COMMITTED , READ UNCOMMITTED , or SERIALIZABLE . 

## • AUTOCOMMIT 

Whether autcommit mode was enabled when the transaction started. 

## • NUMBER_OF_SAVEPOINTS , NUMBER_OF_ROLLBACK_TO_SAVEPOINT , NUMBER_OF_RELEASE_SAVEPOINT 

The number of SAVEPOINT , ROLLBACK TO SAVEPOINT , and RELEASE SAVEPOINT  statements issued during the transaction. 

## • OBJECT_INSTANCE_BEGIN 

Unused. 

## • NESTING_EVENT_ID 

The EVENT_ID  value of the event within which this event is nested. 

## • NESTING_EVENT_TYPE 

The nesting event type. The value is TRANSACTION , STATEMENT , STAGE , or WAIT . ( TRANSACTION does not appear because transactions cannot be nested.) 

The events_transactions_current  table has these indexes: 

•Primary key on ( THREAD_ID , EVENT_ID ) 

TRUNCATE TABLE  is permitted for the events_transactions_current  table. It removes the rows. 

