Database configuration

There is some important index to create on your database to have correct performance on event read / publication.

You should at least have indexes on entity_id, published and sequence_num columns: * entity_id because it’s used by CommandHandler to compute previous state * published because it’s used to load unpublished events before publishing them in Kafka * sequence_num because it’s used to sort events when building previous state

CREATE INDEX app_sequence_num_idx ON app_journal (sequence_num);
CREATE INDEX app_entity_id_idx ON app_journal (entity_id);
CREATE INDEX app_published_idx ON app_journal(published);

Additionally, PostgresEventStore expose loadEventsByQuery method, that allows to query events based on several fields:

  • system_id
  • user_id
  • emission_date

If you plan to use this method, you should also index these columns.

CREATE INDEX app_user_id_idx ON app_journal (user_id);
CREATE INDEX app_system_id_idx ON app_journal (system_id);
CREATE INDEX app_emission_date_idx ON app_journal (emission_date);
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