What is the purpose of `transaction` in SPL?

The purpose of transaction in SPL (Search Processing Language) is to group related events into a single transaction based on defined attributes. This is particularly useful when you have multiple events that share common identifiers or timestamps and represent a single logical action or process. By using the transaction command, you can aggregate these events into a coherent unit, making it easier to analyze complex actions that span several events over time.

For instance, if you are tracking user activity across several logs, you might want to group all the events related to a single user's session into one transaction. By doing so, you can analyze the session as a whole instead of dealing with each event individually, which simplifies the understanding of user behavior or system processes.

This command is essential for scenarios where understanding the relationship and timing between events is critical for the analysis, such as in troubleshooting or performance monitoring. It helps in building metrics about the duration of transactions or the overall success rates based on the grouping of related events.