I am using Debezium with Postgres connector. So far, things are working fine where I can make an update on a table (e.g. List table) and I can see the message via the relevant Kafka topic.
Here is an example of the Debezium message:
{ "before":null, "after":{ "id":"1", "name":"my_list", "userId":3 }, "source":{ "version":"1.6.1.Final", "connector":"postgresql", "name":"my_local_database", "ts_ms":1633012051674, "snapshot":"false", "db":"test_db", "sequence":"["30001968632","30001968632"]", "schema":"sch", "table":"list", "txId":2237, "lsn":30001969096, "xmin":null }, "op":"u", "ts_ms":1633012051737, "transaction":null }
I have a List table which has a one to many relationship with Item (i.e. One List can have multiple Items). The application that uses this database is a Java Application and the List entity is in the form of a POJO:
public class List {
private List<Item>;
...
...
What I would like, is that if there is an update in the item table, then I want Debezium to send me a message containing the updated item data along with with my List data inside the message (as it's a one to many relationship).
My understanding is that I would have to add the 'item' table to the connector config and Debezium will auto-create a topic to listen for item changes - for which I would write Java logic to update my List object above with the updated Item. I was wondering if Debezium has any way of detecting changes in related tables as well (e.g. Item) to the same topic (e.g. the list topic) or whether it can only detect changes on the main table itself (i.e. only the Item table)? I was only concerned with the amount of consumers I would have to create if I had say 10, 20 tables with one to many relationships.