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OSIsoft PI vs QuestDB

OSIsoft PI: The dominant industrial data historian: time-series storage plus asset context for plants and grids. QuestDB: Columnar time-series SQL database built for market data and very high ingest rates.

key differences

  • Licensing: OSIsoft PI is proprietary (Commercial (AVEVA)); QuestDB is open source (permissive) (Apache License 2.0 (open source); Enterprise is commercial).
  • OSIsoft PI is built for larger datasets (≤ 1 PB) than QuestDB (≤ 10 TB).
  • Horizontal scaling is manual in OSIsoft PI and none in QuestDB.
  • Only QuestDB has joins, secondary indexes, materialized views, ttl / expiry, columnar storage.

choose osisoft-pi for

  • +Plant and process historian for OT data
  • +Grid, pipeline and utility network monitoring
  • +Equipment condition monitoring and predictive maintenance feeds
  • +Regulatory records of operational data

best at · Time-series, IoT, Real-time analytics

choose questdb for

  • +Market data and order book analytics
  • +Trading and risk dashboards
  • +Industrial and aerospace telemetry
  • +Crypto exchange tick storage

best at · Time-series, Tick data, Real-time analytics

OSIsoft PIThe dominant industrial data historian: time-series storage plus asset context for plants and grids.
QuestDBColumnar time-series SQL database built for market data and very high ingest rates.
overview
Primary model
Time-Series
Time-Series
Also supports
Hierarchical
Columnar / OLAP, Relational
Type
Database engine
Database engine
Status
Active
Active
Developer
AVEVA (formerly OSIsoft)
QuestDB
First release
1980
2019
Latest version
–
10.1.0 (Oct 22, 2026)
License
ProprietaryCommercial (AVEVA)
Open source (permissive)Apache License 2.0 (open source); Enterprise is commercial
Free tier
—
✓
popularity
WhichDB Score
6.4
34.1
Rank
#362
#60
GitHub stars
–
17.5K
Stack Overflow questions
–
282
scale & guarantees
Comfortable data size
Large (≤ 1 PB)
Medium (≤ 10 TB)
Horizontal scaling
Manual
None
Multi-region
Read replicas
Read replicas
ACID
Limited
Limited
Consistency
Eventual
Strong
Schema
Strict
Flexible
Architecture
Client server, Primary replica
Single node, Primary replica, Client server
deployment
Self-hosted
✓
✓
Vendor-managed cloud
✓
✓
Serverless
—
—
Embedded
—
—
Edge
—
—
Clouds
–
–
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 (PI SQL Data Access), PI Performance Equations
SQL
Client languages
.NET, REST
Java, Python, Go, Rust, C, C++, C#, JavaScript
Best for
Time-series, IoT, Real-time analytics
Time-series, Tick data, Real-time analytics, IoT
Add more to this comparisonNot sure either fits? Try smart match

OSIsoft PI vs QuestDB: FAQ

What is the difference between OSIsoft PI and QuestDB?

OSIsoft PI: The dominant industrial data historian: time-series storage plus asset context for plants and grids. QuestDB: Columnar time-series SQL database built for market data and very high ingest rates. Licensing: OSIsoft PI is proprietary (Commercial (AVEVA)); QuestDB is open source (permissive) (Apache License 2.0 (open source); Enterprise is commercial). OSIsoft PI is built for larger datasets (≤ 1 PB) than QuestDB (≤ 10 TB). Horizontal scaling is manual in OSIsoft PI and none in QuestDB.

When should I choose OSIsoft PI over QuestDB?

Choose OSIsoft PI for plant and process historian for OT data; grid, pipeline and utility network monitoring; and equipment condition monitoring and predictive maintenance feeds. Choose QuestDB for market data and order book analytics; trading and risk dashboards; and industrial and aerospace telemetry.

Is OSIsoft PI or QuestDB more popular?

QuestDB ranks #60 on the WhichDB Score (34.1/100) and OSIsoft PI ranks #362 (6.4/100). Popularity is not fit: check the requirements that matter for your project.

Are OSIsoft PI and QuestDB open source?

No. OSIsoft PI is proprietary, closed-source software. License: Commercial (AVEVA). Yes. QuestDB is open source. License: Apache License 2.0 (open source); Enterprise is commercial.