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Database

Azure Cosmos DB to Azure SQL Database integration — real-time, two-way sync

Keep Azure Cosmos DB and Azure SQL Database in sync without custom scripts. Cut weeks of integration work, eliminate silent data drift, and give your team a single, reliable source of truth.

  • SOC 2 and 6 other compliance frameworks
  • POC with real engineers in minutes

Adopted by fast-scaling companies moving mission-critical data in real time

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Why teams connect Azure Cosmos DB and Azure SQL Database

Keep Azure Cosmos DB and Azure SQL Database synchronized in real time, across engines, regions, or services, in one or both directions.

Two databases that must agree is one of the oldest problems in engineering: different engines for different workloads, separate services with overlapping reference data, a migration in flight, or regional instances that share a subset of records. Hand-rolled replication across systems means change capture, conflict handling, and type mapping, all built and maintained by your team.

Stacksync syncs tables or collections between Azure Cosmos DB and Azure SQL Database continuously and bi-directionally, translating types between the two engines and resolving conflicts by rules you configure. Rows written on either side appear on the other within seconds.

Common use cases

  • Stream operational documents from Cosmos DB into a SQL warehouse via the change feed for analytics without hitting request-unit budgets with full scans.
  • Sync CRM or ERP records into a Cosmos DB container that backs a customer-facing application.
  • Feed an Azure SQL operational database with orders and inventory from an ERP in near real time.
  • Expose SaaS data (billing, support tickets) as tables in Azure SQL for reporting teams already on Microsoft tooling.

Migration with zero-downtime cutover

When one database is replacing the other, sync both directions during the transition and switch traffic when ready, without a freeze window.

Shared reference data between services

Services that own separate databases stay consistent on the records they share, without a custom replication layer.

Regional or environment copies

Mirror selected tables to another region or environment continuously, filtered to just the rows that should travel.

What you can sync between Azure Cosmos DB and Azure SQL Database

Representative objects on each side — any object or custom field can map to any target. Schemas are auto-detected; types are converted between the two systems.

Azure Cosmos DB objects Azure SQL Database objects
Databases Top-level namespaces that scope containers and throughput provisioning. Tables The primary sync target; rows map one-to-one to records in the paired system.
Containers The unit of partitioning and throughput; each container maps to a synced collection. Views Read-only projections used when the sync should expose a curated shape rather than raw tables.
Items (JSON documents) Schema-flexible JSON records read and written during sync; nested structures are flattened or mapped as needed. Schemas Namespaces that organize tables and control which objects a sync user can reach.
Partition keys Determine data distribution and must be included on writes for the sync to route items correctly. Rows and columns Standard relational records with typed columns; primary keys anchor upserts.
Change feed entries Ordered record of inserts and updates per partition, consumed for incremental sync. Stored procedures Existing business logic that some teams invoke on write instead of direct table inserts.
Stored procedures and triggers Server-side logic scoped to a partition; relevant when writes must respect existing validation. Change tracking / CDC tables System-maintained change records used to drive incremental sync.
What ships with Azure Cosmos DB ⇄ Azure SQL Database

Connect Azure Cosmos DB and Azure SQL Database for flexible, real-time data sync.

Real-time sync, workflow automation, event queues, EDI, and monitoring, for every Azure Cosmos DB–Azure SQL Database connection.

Real-time

Two-way sync

Changes in Azure Cosmos DB or Azure SQL Database instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Azure Cosmos DB or Azure SQL Database data changes, update records, fire webhooks, or kick off sequences without brittle API scripts.

At scale

Event queues

Handle millions of events per minute without losing a single Azure Cosmos DB or Azure SQL Database record.

Observability

Monitoring

Track your Azure Cosmos DB ⇄ Azure SQL Database sync health, view errors, and replay failed events in one click.

Trading partners

EDI

Transform legacy EDI complexity into simple database interactions between Azure Cosmos DB and Azure SQL Database.

How the Azure Cosmos DB and Azure SQL Database connectors work

Azure Cosmos DB

Integration surface
REST API and SDKs over HTTPS (API for NoSQL, formerly the SQL API); also MongoDB, Cassandra, Gremlin, and Table API surfaces
Authentication
Account keys, resource tokens, or Microsoft Entra ID role-based access
Change detection
Built-in change feed exposing inserts and updates in order within each partition key range
Capabilities
read · write · CDC

Azure SQL Database

Integration surface
SQL wire protocol (TDS), the same protocol as SQL Server; T-SQL over standard drivers
Authentication
SQL authentication (database credentials) or Microsoft Entra ID authentication
Change detection
Change data capture or change tracking, both supported on Azure SQL Database; polling as a fallback
Capabilities
read · write · CDC
How it works

How to connect Azure Cosmos DB to Azure SQL Database — three steps, no code

Configure and sync within minutes, no code. Whether you sync 50k or 100M+ records, Stacksync handles the queues, infra, and plumbing. Integrations are non-invasive and need zero setup on your systems.

  1. 01

    Connect your apps

    Authenticate Azure Cosmos DB and Azure SQL Database with each platform's native method — OAuth, API keys, or service accounts — plus secure options like SSH tunneling, IP whitelisting, and VPC peering.

    • OAuth 2.0
    • SSH tunnel
    • VPC peering
    Azure Cosmos DB connected
    Azure SQL Database connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Azure Cosmos DB and Azure SQL Database objects to sync — Stacksync auto-detects both schemas, including custom fields where the platform exposes them. Sync to existing tables, or let Stacksync create new ones with ideal data types.

    • Standard objects
    • Custom objects
    • Auto-schema
    objects · Azure Cosmos DB ⇄ Azure SQL Database
    Customers 12,480
    Sales Orders 8,213
    Invoices 5,902
    Items 1,344
  3. 03

    Map fields

    Fields map automatically even when names and types differ. Stacksync handles transformation and type casting for you, zero configuration required.

    • Auto-map
    • Type casting
    • Transforms
    Azure Cosmos DB Azure SQL Database
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
FAQ

Azure Cosmos DB and Azure SQL Database integration FAQ

SECURITY

Security teams love Stacksync

As a data company, we understand the importance of keeping your data secure. Stacksync is built with security best practices to keep your data safe at every layer, and is DPF-certified for US, EU, UK and CH data transfers.

SOC 2 type II
ISO 27001
HIPAA BAA
GDPR
CCPA
CSA STAR
DPF US-EU-UK-CH
→ SECURITY WITH BENEFITS

SSO & SCIM

Let your users access Stacksync from your centralized user management systems. Works with Okta, Azure, Google SSO and more.

Alerts

Immediately get alerted about record syncing issues over email, Slack, PagerDuty and WhatsApp. Resolve issues from a centralized dashboard with retry and revert options.

Secure connection options

Securely connects to your systems with:

Related integrations

Every pair below is a real-time, two-way sync. Search all 386 integrations available for Azure Cosmos DB and Azure SQL Database.

Popular · 8 of 386
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