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IBM Db2 vs Db2 for i

IBM Db2: IBM's enterprise RDBMS for Linux, UNIX, Windows and z/OS, with BLU columnar and pureScale clustering. Db2 for i: The relational database built into IBM i (AS/400), integrated with the OS and object security.

key differences

  • IBM Db2 is built for larger datasets (≤ 1 PB) than Db2 for i (≤ 10 TB).
  • Horizontal scaling is addon in IBM Db2 and none in Db2 for i.
  • Only IBM Db2 has vector search, geospatial, change data capture, columnar storage, in-memory.

choose ibm-db2 for

  • +Mainframe core banking and insurance policy systems
  • +SAP and other packaged apps on IBM infrastructure
  • +Operational data warehouses with BLU columnar tables
  • +Continuous-availability OLTP with pureScale

best at · OLTP, OLAP, Warehouse

choose ibm-db2-for-i for

  • +ERP and distribution systems on IBM i
  • +Regional banking and insurance back ends
  • +Manufacturing execution and warehouse systems
  • +Exposing RPG business logic and data via SQL services and REST

best at · OLTP

IBM Db2IBM's enterprise RDBMS for Linux, UNIX, Windows and z/OS, with BLU columnar and pureScale clustering.
Db2 for iThe relational database built into IBM i (AS/400), integrated with the OS and object security.
overview
Primary model
Relational
Relational
Also supports
Columnar / OLAP, Document, Spatial, Vector, XML
Document
Type
Database engine
Database engine
Status
Active
Active
Developer
IBM
IBM
First release
1983
1988
Latest version
12.1.5 (LUW) (Jun 2026)
IBM i 7.6 TR2 (Jul 2026)
License
ProprietaryProprietary commercial license
ProprietaryProprietary commercial license
Free tier
✓
—
popularity
WhichDB Score
45.5
4.3
Rank
#38
#410
GitHub stars
–
–
Stack Overflow questions
12.9K
999
scale & guarantees
Comfortable data size
Large (≤ 1 PB)
Medium (≤ 10 TB)
Horizontal scaling
Addon
None
Multi-region
Read replicas
Read replicas
ACID
Full
Full
Consistency
Strong
Strong
Schema
Strict
Strict
Architecture
Client server, Primary replica, Shared storage, Distributed
Single node, Multi primary, Shared storage
deployment
Self-hosted
✓
✓
Vendor-managed cloud
✓
✓
Serverless
—
—
Embedded
—
—
Edge
—
—
Clouds
IBM Cloud, AWS
IBM Cloud
capabilities
Transactions
✓
✓
Joins
✓
✓
Secondary indexes
✓
✓
Full-text search
✓
✓
Vector search
✓
—
Geospatial
✓
—
JSON
✓
✓
Change data capture
✓
—
Triggers
✓
✓
Stored procedures
✓
✓
Materialized views
✓
✓
TTL / expiry
—
—
Pub/Sub
—
—
Columnar storage
✓
—
In-memory
✓
—
Durable persistence
✓
✓
Compression
✓
✓
Encryption at rest
✓
✓
Role-based access
✓
✓
Time travel
✓
✓
Branching
—
—
Online schema changes
✓
—
Streaming ingest
—
—
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
SQL, SQL PL
SQL, SQL PL, RPG record-level access
Client languages
Java, C, C#, Python, JavaScript, Go, PHP, Ruby
RPG, COBOL, Java, Python, JavaScript, C#, PHP
Best for
OLTP, OLAP, Warehouse, HTAP
OLTP
Add more to this comparisonNot sure either fits? Try smart match

IBM Db2 vs Db2 for i: FAQ

What is the difference between IBM Db2 and Db2 for i?

IBM Db2: IBM's enterprise RDBMS for Linux, UNIX, Windows and z/OS, with BLU columnar and pureScale clustering. Db2 for i: The relational database built into IBM i (AS/400), integrated with the OS and object security. IBM Db2 is built for larger datasets (≤ 1 PB) than Db2 for i (≤ 10 TB). Horizontal scaling is addon in IBM Db2 and none in Db2 for i. Only IBM Db2 has vector search, geospatial, change data capture, columnar storage, in-memory.

When should I choose IBM Db2 over Db2 for i?

Choose IBM Db2 for mainframe core banking and insurance policy systems; SAP and other packaged apps on IBM infrastructure; and operational data warehouses with BLU columnar tables. Choose Db2 for i for ERP and distribution systems on IBM i; regional banking and insurance back ends; and manufacturing execution and warehouse systems.

Is IBM Db2 or Db2 for i more popular?

IBM Db2 ranks #38 on the WhichDB Score (45.5/100) and Db2 for i ranks #410 (4.3/100). Popularity is not fit: check the requirements that matter for your project.

Are IBM Db2 and Db2 for i open source?

No. IBM Db2 is proprietary, closed-source software. No. Db2 for i is proprietary, closed-source software.