---
title: "Digital Twin Database Options Compared"
description: "Compare digital twin database options: unified Postgres, CrateDB, and multi-database stacks. See tradeoffs, SQL examples, and a real migration case study. "
section: "Postgres for IoT"
published: 2026-09-30T19:24:07.774Z
updated: 2026-09-23T00:00:00.000Z
---

*Updated at Sep 23, 2026*

> **TimescaleDB is now Tiger Data.**

## The Short Answer

The best digital twin database is a unified, Postgres-based time-series database that natively handles high-frequency telemetry, relational asset context, and spatial or vector data in one system. The alternatives are a distributed SQL database like CrateDB, or a specialized time-series database paired with separate relational and vector stores, each trading that simplicity for operational overhead of its own.

## What a Digital Twin's Data Layer Actually Needs

A digital twin's storage layer does three jobs at once. It ingests high-frequency time-series telemetry, sensor readings, vibration, temperature, machine state, often multiple times per second per asset, the same need a [<u>plant historian</u>](https://www.tigerdata.com/learn/plant-historian) serves in industrial settings.

It also needs relational asset context: which sensor belongs to which equipment, its maintenance history, and where it sits in a plant hierarchy. And as digital twins mature, they increasingly need spatial or vector data too: asset positions for facility twins, or embeddings for anomaly matching against historical states.

Most teams default to three separate systems: time-series, relational, and sometimes vector. Each choice is defensible alone, but the cost shows up in the seams: three systems to provision and monitor, plus pipelines to sync them and application code to stitch one answer back together.

That's a different question from which digital twin *platform* to use. Azure Digital Twins, NVIDIA Omniverse, and simulation or CAD software sit at the application layer. This article covers the data layer underneath: the database that stores and serves what those platforms consume, regardless of which platform you choose.

### Digital Twin vs. Digital Shadow: Does It Change the Data Requirements?

A digital shadow is typically one-way: sensor data updates a model, but the model doesn't act back on the asset. A full digital twin adds bidirectional control.

That distinction matters for control-system architecture, not for the data layer. Both need time-series, relational, and often spatial or vector data stored and queried together, so the decision below applies to either.

## Comparing Your Options: Unified Postgres, CrateDB, or a Multi-Database Stack

A disclosure up front: Tiger Data sells a Postgres-based time-series product, so we have a stake here. What follows represents each option's real strengths and limitations, not a one-sided pitch. Comparative performance claims below use directional language, since no independent benchmark exists between Tiger Data and CrateDB for digital twin workloads.

| **Unified Postgres (Tiger Data)** | **CrateDB (distributed SQL)** | **Multi-database stack** |
| --- | --- | --- |
| Query language | Standard SQL | SQL over a flexible document model | SQL, plus each system's own query language |
| Schema flexibility | Structured tables; JSONB for irregular fields | Schema-less by default, native JSON handling | Varies per system |
| Time-series approach | Hypertables, automatic partitioning, compression | Time-based partitioning within a distributed cluster | Purpose-built time-series engine (e.g., InfluxDB) |
| Relational/join support | Native SQL joins across tables | SQL joins across a distributed cluster | Cross-system joins require application-level stitching |
| Spatial support | PostGIS | Basic geo types | Depends on component chosen |
| Vector/embedding support | pgvector | Not a core focus | Separate vector database required |
| Operational overhead | One system to run | One system to run | Three systems to deploy, secure, and monitor |
| Deployment options | Self-hosted or managed (Tiger Cloud) | Self-hosted or managed cloud | Varies per component |
| Best-fit scale | Most digital twin workloads, including large fleets with read replicas | Very large, horizontally sharded clusters | Teams with one component already deeply entrenched |

### Unified Postgres: Hypertables, Compression, pgvector, and PostGIS in One Database

This approach runs all three data types in one Postgres instance: TimescaleDB [<u>hypertables</u>](https://www.tigerdata.com/docs/learn/hypertables/understand-hypertables) for telemetry, standard relational tables for asset and maintenance context, and PostGIS or pgvector for spatial and embedding data, all queryable with standard SQL, including joins across tables in one query.

On Tiger Cloud, pgvector is enabled by default, while PostGIS is enabled per service with a single CREATE EXTENSION postgis. 

The strengths are practical. Teams keep the SQL, tooling, and hiring pool they already have. There's one system to operate instead of three, and no cross-database query layer for a dashboard that needs telemetry alongside maintenance history.

The limitations are real too. This is still a single-engine architecture. Extremely high-cardinality workloads or fleets at massive scale may eventually need read replicas or a managed scaling path through Tiger Cloud. And if sensor payloads are so irregular that even a JSONB column doesn't fit well, a schema-less model may suit better. For the full schema design, compression strategy, and PostGIS and pgvector walkthrough, see the [<u>full digital twin architecture guide</u>](https://www.tigerdata.com/learn/digital-twin-architecture); this is the short decision-guide version.

### CrateDB: A Distributed SQL Alternative

CrateDB is a distributed SQL database with a flexible, schema-less document model and PostgreSQL wire-protocol compatibility, positioned for digital twin telemetry. Its real strengths: schema flexibility for frequently changing payloads, SQL access over that flexible model, and a distributed architecture built for horizontal scale.

The limitations are worth naming directly. CrateDB's own public content on digital twins doesn't include SQL examples or a schema walkthrough for the use case. It doesn't publish a named comparison against other databases, despite positioning itself as a resource for choosing between options. Its customer proof is a soft, third-party mention, not an independently verified case study. Treat CrateDB's marketing claims as its own stated positioning, not confirmed benchmarks.

### The Multi-Database Stack: Time-Series DB + Relational DB + Vector DB

This pattern pairs a purpose-built time-series database (commonly InfluxDB) with a separate relational database for asset context, and sometimes a vector database for anomaly detection.

Each component can be best-in-class for its workload, and a team already running one may only need to add another rather than migrate everything. The tradeoff is operational: three systems to deploy and sync, and questions like "show telemetry alongside maintenance history" require application-level stitching instead of one SQL query. InfluxDB's product line has also split across several generations and tiers, which tends to add migration planning a single-database approach avoids.

## A Representative Schema for Digital Twin Data

Here's a focused example, not a full implementation, showing one asset's telemetry and context in a single Postgres schema: a hypertable for readings, a relational table for asset metadata, and a join query bringing them together.

`CREATE TABLE assets (
  asset_id TEXT PRIMARY KEY,
  asset_type TEXT NOT NULL,
  location TEXT,
  install_date DATE
);

CREATE TABLE sensor_readings (
  time TIMESTAMPTZ NOT NULL,
  asset_id TEXT NOT NULL,
  temperature DOUBLE PRECISION,
  vibration DOUBLE PRECISION
);

SELECT create_hypertable(
  'sensor_readings',
  by_range('time')
);

-- Join telemetry with asset context
SELECT
  r.time,
  a.asset_type,
  a.location,
  r.temperature,
  r.vibration
FROM sensor_readings r
JOIN assets a
  ON r.asset_id = a.asset_id
WHERE r.time > now() - INTERVAL '1 day'
ORDER BY r.time DESC;`

A [<u>continuous aggregate</u>](https://www.tigerdata.com/docs/learn/continuous-aggregates) illustrates how real-time rollups work without a separate ETL pipeline:

`CREATE MATERIALIZED VIEW asset_hourly_avg
WITH (timescaledb.continuous) AS
SELECT
  asset_id,
  time_bucket('1 hour', time) AS bucket,
  avg(temperature) AS avg_temp
FROM sensor_readings
GROUP BY asset_id, bucket;`

This is a sketch, not the full implementation guide. For the complete schema design, compression policy, and PostGIS and pgvector treatment, see the [<u>full digital twin architecture guide</u>](https://www.tigerdata.com/learn/digital-twin-architecture).

## Real-World Proof: Mechademy's Digital Twin Migration

Mechademy builds hybrid digital twins for industrial equipment, combining physics-based turbomachinery models with machine learning diagnostics to monitor critical assets for oil, gas, and energy companies. Their original stack ran on MongoDB, chosen for its early flexibility. As diagnostic workloads matured, they needed time-aligned data at multiple resolutions, from 15-second raw streams to hourly summaries. MongoDB had no native time-series support, so the team built manual bucketing workarounds that turned into brittle, expensive-to-operate pipelines, with CPU utilization on small tenants climbing above 95%.

After migrating to Tiger Data, using hypertables, continuous aggregates, and native compression on standard SQL, Mechademy cut infrastructure costs by 87% and increased supported workload 50x, from 200,000 to 10 million tests per half hour. This is Tiger Data's own verified customer data, not a comparative claim against CrateDB, and the kind of named, numbers-backed proof point largely absent elsewhere in this category. Read the [<u>full Mechademy case study</u>](https://www.tigerdata.com/blog/how-mechademy-cut-hybrid-digital-twin-infrastructure-costs) for the complete details.

## Decision Framework: Which Should You Choose?

### Choose a Unified Postgres Database (Tiger Data) if:

- You want time-series, relational, and spatial or vector data queryable together with standard SQL, without operating multiple systems.
- Your team already has Postgres expertise and wants to avoid a new query language.
- You need joins between sensor data and asset or maintenance history in the same query.
- You want a managed scaling path, like Tiger Cloud's read replicas, without re-architecting to a distributed system.

### Choose CrateDB if:

- Your sensor payloads are highly irregular or frequently changing shape, and you want a schema-less model with SQL access.
- You're already running or evaluating a distributed SQL architecture for reasons beyond this workload.
- You're comfortable building your own comparison and proof points, since CrateDB's public material doesn't provide a worked digital twin example.

### Choose a Multi-Database Stack if:

- You already have significant investment in a purpose-built time-series database and only need to add one adjacent capability, like vector search.
- Your components have genuinely divergent scaling requirements that make a single-engine approach impractical.
- Your team has the operational capacity to run and keep multiple database systems in sync.

## Migrating to a Unified Postgres Digital Twin Database

Teams tend to arrive here through one of three paths: consolidating from MongoDB once time-series demands outgrow manual workarounds (the Mechademy pattern), consolidating from a specialized time-series database once relational or spatial needs grow, or starting fresh with one system instead of three. This is the same consolidation pattern behind most [<u>manufacturing analytics database</u>](https://www.tigerdata.com/learn/manufacturing-analytics-database) migrations, where digital twin telemetry is one workload among several.

A realistic migration means mapping your schema to hypertables and relational tables, backfilling historical telemetry, and cutting over once validated against production traffic. PostgreSQL wire-protocol compatibility, shared by Tiger Data and CrateDB, tends to ease application-layer work compared to moving off a document database, where query patterns often need rewriting. If you're still scoping requirements before committing, the [<u>IIoT database requirements</u>](https://www.tigerdata.com/learn/iiot-database-requirements) page is a useful starting point.