1. Database Reference
  2. Dynamic Performance Views
  3. Dynamic Performance (V$) Views: V$SCHEDULER_RUNNING_JOBS to V$ZONEMAP_USAGE_STATS
  4. V$STANDBY_EVENT_HISTOGRAM

9.79 V$STANDBY_EVENT_HISTOGRAM

V$STANDBY_EVENT_HISTOGRAM displays the histogram of apply lag on the physical standby. Each distinct value of apply lag has its own bucket and the count in the corresponding bucket represents the number of occurrences so far. The physical standby samples the apply lag every second and increments the corresponding bucket in the histogram.
Column Datatype Description

NAME

VARCHAR2(64)

Name of the event (currently APPLY LAG is the only valid value)

TIME

NUMBER

Time duration that the bucket represents

UNIT

VARCHAR2(16)

Time unit (seconds, minutes, hours, or days)

COUNT

NUMBER

Each row is a histogram bucket for apply lag. COUNT is the number of occurrences the apply lag falls into the histogram bucket.

LAST_TIME_UPDATED

VARCHAR2(20)

Last time the bucket was updated by an event falling into that time duration

CON_ID

NUMBER

The ID of the container to which the data pertains. Possible values include:

  • 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

  • 1: This value is used for rows containing data that pertain to only the root

  • n: Where n is the applicable container ID for the rows containing data