4.289 DBA_HIST_ASH_SNAPSHOT

DBA_HIST_ASH_SNAPSHOT provides the list of snapshots that contains Active Session History (ASH) data.

This view differs from DBA_HIST_SNAPSHOT in that it provides snapshots which had errors flushing some Automatic Workload Repository (AWR) tables, but for which ASH data may be successfully flushed (DBA_HIST_SNAPSHOT filters out snapshots which had errors flushing AWR tables).

Column Datatype NULL Description

SNAP_ID

NUMBER

NOT NULL

Unique snapshot ID

DBID

NUMBER

NOT NULL

Database ID for the snapshot

INSTANCE_NUMBER

NUMBER

NOT NULL

Instance number for the snapshot

STARTUP_TIME

TIMESTAMP(3)

NOT NULL

Startup time of the instance

BEGIN_INTERVAL_TIME

TIMESTAMP(3)

NOT NULL

Time at the beginning of the snapshot interval

END_INTERVAL_TIME

TIMESTAMP(3)

NOT NULL

Time at the end of the snapshot interval; the actual time the snapshot was taken

FLUSH_ELAPSED

INTERVAL DAY(5) TO SECOND(1)

Amount of time to perform the snapshot

SNAP_LEVEL

NUMBER

Snapshot level

STATUS

NUMBER

Indicates if the snapshot was successfully flushed without any errors. Possible values:

  • 0 - No errors

  • 1 - Errors on some AWR tables

ERROR_COUNT

NUMBER

Number of errors occurring in the tables for the particular snapshot

BL_MOVED

NUMBER

Reserved for internal use

SNAP_FLAG

NUMBER

Condition under which the snapshot was inserted. Possible values are:

  • 1 - Manual snapshot created using a PL/SQL package

  • 2 - Imported snapshot

  • 4 - Snapshot taken while Diagnostic Pack or Tuning Pack was not enabled

SNAP_TIMEZONE

INTERVAL DAY(0) TO SECOND(0)

Snapshot time zone expressed as offset from UTC (Coordinated Universal Time) time zone

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

See Also:

"DBA_HIST_SNAPSHOT"