Event Structure¶

Events have two parts: payload (the data) and metadata (routing info).

Payload¶

The event body sent to your sink. Contains the row data and trigger context.

{
  "tg_name": "user-created",
  "tg_op": "INSERT",
  "tg_table_name": "users",
  "tg_table_schema": "public",
  "timestamp": 1703001234567,
  "new": {
    "id": 123,
    "email": "user@example.com"
  }
}

Selecting Columns¶

By default, all columns are included. Use column_names to select specific columns:

INSERT INTO pgstream.subscriptions (key, stream_id, operation, schema_name, table_name, column_names)
VALUES ('user-created', 1, 'INSERT', 'public', 'users', ARRAY['id', 'email']);

Metadata¶

Routing configuration read by sinks. Controls where and how events are delivered.

INSERT INTO pgstream.subscriptions (key, stream_id, operation, schema_name, table_name, metadata)
VALUES ('user-created', 1, 'INSERT', 'public', 'users', '{"topic": "users", "priority": "high"}');

Each sink reads specific metadata fields:

See Extensions to compute payload and metadata values dynamically.