What is the exact meaning of the parameter database.history on Debezium?

We are working on a project using Debezium to Stream data from a Database reading the binlog to a message broker. Working on it a bit deeper, and trying to understand better the tool, two questions related the configuration parameters came up:

• What is exact meaning of the parameter database.history?
• And what is the differences between the possible values MemoryDatabaseHistory and FileDatabaseHistory?

Thanks!

database history serves to record evolution of database schema over the time. It is used by Debezium to create a correct data from historical event in case the schema in database has been changed. MemoryDatabaseHistory should be used only for testing as it does not survive restart. FileDatabaseHistory should be used only for Debezium Embedded. If you use Debezium iniside Kafka Connect then you should use KafkaDatabaseHistory.