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Database

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

Keep Azure Cosmos DB and SQL Server 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 SQL Server

Keep Azure Cosmos DB and SQL Server 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 SQL Server 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

  • Two-way sync between a Cosmos DB-backed product catalog and a PIM or commerce platform.
  • Consolidate documents from multiple containers into a single reporting store.
  • Consolidate branch or plant databases into a single operational SQL Server hub
  • Bi-directional sync between SQL Server rows and CRM objects so .NET line-of-business apps and sales tools share one dataset

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.

Cross-engine sync

Keep the same dataset live in both Azure Cosmos DB and SQL Server, so each workload runs on the engine that suits it.

What you can sync between Azure Cosmos DB and SQL Server

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 SQL Server objects
Partition keys Determine data distribution and must be included on writes for the sync to route items correctly. Views Read-side projections used as outbound sync sources.
Change feed entries Ordered record of inserts and updates per partition, consumed for incremental sync. Columns Field-level mapping targets with T-SQL types.
Stored procedures and triggers Server-side logic scoped to a partition; relevant when writes must respect existing validation. Primary and Unique Keys Match keys for idempotent upserts and conflict handling.
Databases Top-level namespaces that scope containers and throughput provisioning. CDC Change Tables System-populated tables holding captured inserts, updates, and deletes for consumers.
Containers The unit of partitioning and throughput; each container maps to a synced collection. Stored Procedures T-SQL logic that can validate or post-process synced rows.
Items (JSON documents) Schema-flexible JSON records read and written during sync; nested structures are flattened or mapped as needed. Databases Instance-level databases that scope a sync's reads and writes.
What ships with Azure Cosmos DB ⇄ SQL Server

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

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

Real-time

Two-way sync

Changes in Azure Cosmos DB or SQL Server 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 SQL Server 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 SQL Server record.

Observability

Monitoring

Track your Azure Cosmos DB ⇄ SQL Server 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 SQL Server.

How the Azure Cosmos DB and SQL Server 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

SQL Server

Integration surface
SQL over the TDS wire protocol (Tabular Data Stream), via ODBC/JDBC/ADO.NET drivers
Authentication
Database credentials entered as a connection string or as parameters (host/user/password) in the Create New Sync page
Change detection
SQL Server Native Change Data Capture (CDC); a DBA runs a one-time setup script with sysadmin privileges to enable CDC and create Stacksync wrapper procedures
Capabilities
read · write · CDC
Rate limits
No API rate limits; throughput depends on instance resources, licensing tier, and connection limits
SQL Server setup guide
How it works

How to connect Azure Cosmos DB to SQL Server — 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 SQL Server 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
    SQL Server connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Azure Cosmos DB and SQL Server 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 ⇄ SQL Server
    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 SQL Server
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
FAQ

Azure Cosmos DB and SQL Server 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 SQL Server.

Popular · 8 of 386
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