When is the on-run-start hook executed in dbt?

The on-run-start hook is executed at the very beginning of a dbt run, which includes dbt commands such as dbt run, dbt seed, or dbt snapshot. This hook allows users to implement custom logic or tasks that they want to execute right at the start of these processes.

For instance, you might want to set up specific configurations, log initial information, or run certain setup scripts that are necessary before the actual models, seeds, or snapshots are processed. Thus, this hook serves as a crucial point for any preparatory activities that need to occur before the main logic of the dbt commands begins.

The other options outline different phases of the dbt workflow. For example, a conclusion of a run does not come into play when discussing the on-run-start hook, as it specifically pertains to initialization rather than completion. Similarly, tasks following the execution of models or during the execution phase are outside the scope of what the on-run-start hook is designed to manage.