PostgreSQL to Oracle
real-time replication
TwinCommit replicates PostgreSQL to Oracle Database in real time by reading the PostgreSQL transaction log and applying every committed change exactly once and in commit order. Use it to migrate or continuously mirror PostgreSQL into Oracle with zero downtime, with no triggers or capture tables on the source.
PostgreSQL
log reader
commit-ordered · exactly-once
Oracle
native writer
How capture works on PostgreSQL
TwinCommit uses a logical replication slot with the built-in pgoutput plugin, so there is nothing to install on the server.
Prerequisites
- ✓wal_level = logical
- ✓REPLICATION privilege
- ✓Primary key or REPLICA IDENTITY FULL
How apply works on Oracle
Array-bound MERGE statements committed together with the TwinCommit checkpoint table in one transaction.
Requirements
- ✓ARCHIVELOG mode
- ✓Minimal plus primary-key supplemental logging
- ✓Read access to V$ views and the archive destination
Setup
Set up PostgreSQL → Oracle in four steps
- 1
Prepare PostgreSQL
Run twincommit check. It verifies wal_level = logical and the other prerequisites, and prints the exact fix for anything missing.
- 2
Point at Oracle
Add a target block for Oracle. 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: postgres
dsn: ${SOURCE_DSN}
slot: twincommit
target:
type: oracle
dsn: ${ORACLE_TARGET_DSN}
schema: REPLICA
tables:
- source: SALES.ORDERS
- source: SALES.ORDER_LINES
exclude_columns: [INTERNAL_NOTES]PostgreSQL to Oracle replication FAQ
How does TwinCommit replicate PostgreSQL to Oracle?
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TwinCommit reads changes from the PostgreSQL transaction log, buffers them per transaction, and applies each committed transaction to Oracle in commit order. Array-bound MERGE statements committed together with the TwinCommit checkpoint table in one transaction.
Does PostgreSQL to Oracle replication need triggers or capture tables?
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No. TwinCommit reads the PostgreSQL log directly and creates no objects in the source database.
Is PostgreSQL to Oracle replication exactly-once?
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Yes. TwinCommit commits its checkpoint in the same Oracle transaction as the data, so a crash or restart never loses or duplicates a transaction.
What PostgreSQL versions are supported?
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PostgreSQL 13–18 · Amazon RDS and Aurora · Azure Flexible Server · Cloud SQL · AlloyDB.
Stream PostgreSQL to Oracle today.
Download the free Developer edition, or have one of our replication engineers walk you through a migration plan.