Performance Schema Statement Event Tables Of the tables that contain statement event rows,  events_statements_current  is the most fundamental. Other tables that contain statement event rows are logically derived from the current events. For example, the  events_statements_history  and  events_statements_history_long  tables are collections of the most recent statement events that have ended, up to a maximum number of rows per thread and globally across all threads, respectively. For more information about the relationship between the three  events_statements_ xxx  event tables, see Section 27.9, “Performance Schema Tables for Current and Historical Events” . For information about configuring whether to collect statement events, see Section 27.12.6, “Performance Schema Statement Event Tables” . The  events_statements_current  table has these columns: The thread associated with the event and the thread current event number when the event starts. The THREAD_ID  and  EVENT_ID  values taken together uniquely identify the row. No two rows have the same pair of values. This column is set to  NULL  when the event starts and updated to the thread current event number when the event ends. The name of the instrument from which the event was collected. This is a  NAME  value from the setup_instruments  table. Instrument names may have multiple parts and form a hierarchy, as discussed in Section 27.6, “Performance Schema Instrument Naming Conventions” . For SQL statements, the  EVENT_NAME  value initially is  statement/com/Query  until the statement is parsed, then changes to a more appropriate value, as described in Section 27.12.6, “Performance Schema Statement Event Tables” . 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. 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” . • THREAD_ID ,  EVENT_ID • END_EVENT_ID • EVENT_NAME • SOURCE • TIMER_START ,  TIMER_END ,  TIMER_WAIT • LOCK_TIME 4974