What does Transaction logging and Transaction summary mean, compression data after mean?

UIM 8.x
nas 4.x / 9.0

Transaction Logging

This module is only started if the NAS transaction logging is activated.
It converts internal events to database records stored in the transactionlog database (transactionlog.db).
The following tables are maintained by the transaction logger:

NAS_TRANSACTION_LOG Stores the actual alarm event as received and processed by the NAS.
This is enabled by the ‘Log transaction details’ flag.

Compression
'Compression' is done by removing suppressed updates. Houskeeping is done by removing the entire transaction.

NAS_TRANSACTION_SUMMARY
One record per unique alarm is maintained and updated.
Housekeeping is done by removing the alarm record.

The Alarm Server is capable of logging all steps in the life of an alarm (the alarm transaction) from the alarm are generated until it is acknowledged.

nas settings to understand and be aware of are:

Compress transactions after
The events (of type suppression) for alarms stored in the transaction log will be deleted after the number of days specified.

The default is 7 days.

Keep transaction history
For how long (in days) the transaction history is stored.The transaction history stores all events for each of the alarms handled by the NAS in the database.

Keep transaction summary
For how long (in days) the transaction summary is stored.

The default value is 30 days.

The transaction summary for each alarm is stored as one row in the database.

If nas -> Setup -> Transaction Log -> 'Activate transaction-logging' is checked, then the settings for 'Compress transactions', 'transaction history' and 'transaction summary' will be used.

The alarms live in two diferent places: In nas, (the alarm subconsole), active alarms are in the database.db file, and historical data (cleared alerts) in the transactionlog.db file.
This is actually an SQLite database and a free SQLite browser can be used to query against and extract the data.

In the Alarm Console in UMP, the data is pulled from the NAS_ALARMS table (active alarms), the NAS_TRANSACTION_LOG table (transaction history) and NAS_TRANSACTION_SUMMARY table (transaction summary).

So you can query against both of those 'transaction' tables, but be aware that the data will only be stored as long as the 'Transaction Log Management' time periods have specified.

Where are the alarms stored in UIM?

What do the time related fields mean in the Alarm Tables in UIM?

nas Transaction Logging/Transaction Summary and compression

What is the meaning of the of nas alarm Subjects?

Nas alarm counts are not in sync between UMP USM and the Infrastructure Manager alarm subconsole

Why do some alarms' "count" increase immediately in the alarm console while others don't show the count increasing even when the alarms are suppressed?

Nas (alarm server) documentation