• db4.t5  events are monitored 

Similar logic applies for combining the TIMED  columns from the setup_instruments  and setup_objects  tables to determine whether to collect event timing information. 

If a persistent table and a temporary table have the same name, matching against setup_objects rows occurs the same way for both. It is not possible to enable monitoring for one table but not the other. However, each table is instrumented separately. 

## 27.4.6 Pre-Filtering by Thread 

The threads  table contains a row for each server thread. Each row contains information about a thread and indicates whether monitoring is enabled for it. For the Performance Schema to monitor a thread, these things must be true: 

•The thread_instrumentation  consumer in the setup_consumers  table must be YES . 

•The threads.INSTRUMENTED  column must be YES . 

•Monitoring occurs only for those thread events produced from instruments that are enabled in the setup_instruments  table. 

The threads  table also indicates for each server thread whether to perform historical event logging. This includes wait, stage, statement, and transaction events and affects logging to these tables: 

events_waits_history events_waits_history_long events_stages_history events_stages_history_long events_statements_history events_statements_history_long events_transactions_history events_transactions_history_long 

For historical event logging to occur, these things must be true: 

•The appropriate history-related consumers in the setup_consumers  table must be enabled. For example, wait event logging in the events_waits_history  and events_waits_history_long tables requires the corresponding events_waits_history  and events_waits_history_long consumers to be YES . 

•The threads.HISTORY  column must be YES . 

•Logging occurs only for those thread events produced from instruments that are enabled in the setup_instruments  table. 

For foreground threads (resulting from client connections), the initial values of the INSTRUMENTED  and HISTORY  columns in threads  table rows are determined by whether the user account associated with a thread matches any row in the setup_actors  table. The values come from the ENABLED  and HISTORY columns of the matching setup_actors  table row. 

For background threads, there is no associated user. INSTRUMENTED  and HISTORY  are YES  by default and setup_actors  is not consulted. 

The initial setup_actors  contents look like this: 

mysql> SELECT * FROM performance_schema.setup_actors; +------+------+------+---------+---------+ 

