SQL Server to Db2
real-time replication
TwinCommit replicates Microsoft SQL Server to IBM Db2 in real time by reading the SQL Server transaction log and applying every committed change exactly once and in commit order. Use it to migrate or continuously mirror SQL Server into Db2 with zero downtime, with no triggers or capture tables on the source.
SQL Server
log reader
commit-ordered · exactly-once
Db2
native writer
How capture works on SQL Server
TwinCommit reads the active and backed-up transaction log directly, so you do not need SQL Server Agent CDC jobs or change tables.
Prerequisites
- ✓FULL recovery model
- ✓Primary key on each replicated table
- ✓VIEW SERVER STATE and db_owner on the source database
How apply works on Db2
Array MERGE statements committed in the same unit of work as the TwinCommit checkpoint.
Requirements
- ✓Archive logging enabled (LOGARCHMETH1)
- ✓DATA CAPTURE CHANGES on each replicated table
- ✓A primary key or unique index on each replicated table
- ✓DBADM (or SYSADM) for the capture user
Setup
Set up SQL Server → Db2 in four steps
- 1
Prepare SQL Server
Run twincommit check. It verifies full recovery model and the other prerequisites, and prints the exact fix for anything missing.
- 2
Point at Db2
Add a target block for Db2. 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: sqlserver
dsn: ${SOURCE_DSN}
target:
type: db2
database: REPLDB
user: ${DB2_TARGET_USER}
password: ${DB2_TARGET_PASSWORD}
tables:
- source: SALES.ORDERS
- source: SALES.ORDER_LINES
exclude_columns: [INTERNAL_NOTES]SQL Server to Db2 replication FAQ
How does TwinCommit replicate SQL Server to Db2?
+
TwinCommit reads changes from the SQL Server transaction log, buffers them per transaction, and applies each committed transaction to Db2 in commit order. Array MERGE statements committed in the same unit of work as the TwinCommit checkpoint.
Does SQL Server to Db2 replication need triggers or capture tables?
+
No. TwinCommit reads the SQL Server log directly and creates no objects in the source database.
Is SQL Server to Db2 replication exactly-once?
+
Yes. TwinCommit commits its checkpoint in the same Db2 transaction as the data, so a crash or restart never loses or duplicates a transaction.
What SQL Server versions are supported?
+
SQL Server 2016–2025 · Azure SQL Managed Instance · Azure SQL Database (target).
Stream SQL Server to Db2 today.
Download the free Developer edition, or have one of our replication engineers walk you through a migration plan.