[STREAM] REST_API → batch_001
{ "id": "USR_001", "name": "Alex Carter", email": null, "ts": "2024-01-15T08:22:01Z" }
{ "id": "USR_002", "name": "Sarah Miller", "email": "sarah@data.io", "ts": "2024-01-15T08:22:05Z" }
{ "id": "USR_001", "name": "alex carter", /* DUPLICATE */ "email": "alex@data.io" }

[STREAM] SQL_DB → snapshot_v2
SELECT * FROM users WHERE region = 'APAC';
ERROR: last_login = "undefined" -- row 412
MISSING_FIELD: status -- row 2091

[STREAM] KAFKA → realtime_events
{ "event": "purchase", "amount": 142.50, "currency": "USD", "user_id": "USR_042" }
{ "event": "purchase", "amount": 142.50, /* DUPLICATE */ "user_id": "USR_042" }
{ "event": "login", "timestamp": "NaN", "user_id": "USR_099" }