Oracle to Kafka
real-time replication
TwinCommit replicates Oracle Database to Apache Kafka in real time by reading the Oracle transaction log and applying every committed change exactly once and in commit order. Use it to publish every committed Oracle change as an event stream, with no triggers or capture tables on the source.
Oracle
log reader
commit-ordered · exactly-once
Kafka
native writer
How capture works on Oracle
TwinCommit parses online redo and archived logs directly, including RAC threads, and reassembles transactions in SCN order before they leave the host.
Prerequisites
- ✓ARCHIVELOG mode
- ✓Minimal plus primary-key supplemental logging
- ✓Read access to V$ views and the archive destination
How apply works on Kafka
Each source transaction is published with Kafka transactions, so consumers using read_committed never see a partial transaction. Messages are keyed by primary key in JSON, Avro or Protobuf.
Requirements
- ✓A topic naming template
- ✓Producer ACLs including transactional.id
- ✓Optional Schema Registry for Avro and Protobuf
Setup
Set up Oracle → Kafka in four steps
- 1
Prepare Oracle
Run twincommit check. It verifies archivelog mode and the other prerequisites, and prints the exact fix for anything missing.
- 2
Point at Kafka
Add a target block for Kafka. TwinCommit can generate target DDL with twincommit ddl -apply.
- 3
Snapshot
twincommit snapshot copies each table under a brief share lock and records the exact log position.
- 4
Stream
twincommit run streams every committed change from that position, exactly once and in commit order.
source:
type: oracle
database: PRODDB
user: ${SRC_USER}
password: ${SRC_PASSWORD}
target:
type: kafka
bootstrap_servers: broker-1:9092,broker-2:9092
topic: "{schema}.{table}"
format: avro
schema_registry: http://registry:8081
tables:
- source: SALES.ORDERS
- source: SALES.ORDER_LINES
exclude_columns: [INTERNAL_NOTES]Oracle to Kafka replication FAQ
How does TwinCommit replicate Oracle to Kafka?
+
TwinCommit reads changes from the Oracle transaction log, buffers them per transaction, and applies each committed transaction to Kafka in commit order. Each source transaction is published with Kafka transactions, so consumers using read_committed never see a partial transaction. Messages are keyed by primary key in JSON, Avro or Protobuf.
Does Oracle to Kafka replication need triggers or capture tables?
+
No. TwinCommit reads the Oracle log directly and creates no objects in the source database.
Is Oracle to Kafka replication exactly-once?
+
Yes. TwinCommit commits its checkpoint in the same Kafka transaction as the data, so a crash or restart never loses or duplicates a transaction.
What Oracle versions are supported?
+
Oracle 19c, 21c, 23ai · RAC, Data Guard standby, CDB/PDB · Autonomous Database (target).
Use cases for this route
Related replication routes
Stream Oracle to Kafka today.
Download the free Developer edition, or have one of our replication engineers walk you through a migration plan.