Oracle to MariaDB
real-time replication
TwinCommit replicates Oracle Database to MariaDB in real time by reading the Oracle transaction log and applying every committed change exactly once and in commit order. Use it to migrate or continuously mirror Oracle into MariaDB with zero downtime, with no triggers or capture tables on the source.
Oracle
log reader
commit-ordered · exactly-once
MariaDB
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 MariaDB
Multi-row INSERT … ON DUPLICATE KEY UPDATE and DELETE batches, committed with the checkpoint in one transaction.
Requirements
- ✓binlog_format = ROW and binlog_row_image = FULL
- ✓REPLICATION SLAVE and BINLOG MONITOR grants
- ✓log_slave_updates on Galera nodes
Setup
Set up Oracle → MariaDB 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 MariaDB
Add a target block for MariaDB. 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: mariadb
dsn: ${MARIADB_DSN}
database: replica
tables:
- source: SALES.ORDERS
- source: SALES.ORDER_LINES
exclude_columns: [INTERNAL_NOTES]Oracle to MariaDB replication FAQ
How does TwinCommit replicate Oracle to MariaDB?
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TwinCommit reads changes from the Oracle transaction log, buffers them per transaction, and applies each committed transaction to MariaDB in commit order. Multi-row INSERT … ON DUPLICATE KEY UPDATE and DELETE batches, committed with the checkpoint in one transaction.
Does Oracle to MariaDB replication need triggers or capture tables?
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No. TwinCommit reads the Oracle log directly and creates no objects in the source database.
Is Oracle to MariaDB replication exactly-once?
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Yes. TwinCommit commits its checkpoint in the same MariaDB transaction as the data, so a crash or restart never loses or duplicates a transaction.
What Oracle versions are supported?
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Oracle 19c, 21c, 23ai · RAC, Data Guard standby, CDB/PDB · Autonomous Database (target).
Stream Oracle to MariaDB today.
Download the free Developer edition, or have one of our replication engineers walk you through a migration plan.