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Data warehouse ⇄ Database

MotherDuck to SQL Server integration — real-time, two-way sync

Keep MotherDuck 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 MotherDuck and SQL Server

Connect SQL Server and MotherDuck with one live, two-way sync: operational rows flow into the warehouse, and computed results flow back where systems can read them fast.

Operational databases and analytical warehouses want the same data at different moments. Analysts want SQL Server's rows in MotherDuck, current and joinable, without a change-data-capture pipeline to maintain. Engineers want the outputs of warehouse work, such as aggregates, features, and segments, available in SQL Server where the services that read from it get them at normal query latency.

Stacksync covers both directions with one connection. Tables or collections in SQL Server sync into MotherDuck in real time, and result tables in MotherDuck sync back into SQL Server, with schema and type mapping between the two systems handled for you.

Common use cases

  • Sync modeled MotherDuck tables outward to operational tools for activation
  • Share curated, synced datasets with other teams through read-only database shares
  • Expose SaaS records as SQL Server tables that existing SSRS reports and internal apps can query
  • Mirror on-premises ERP data held in SQL Server into cloud CRM and support systems

Serve warehouse results at database speed

Aggregates or model outputs computed in MotherDuck sync into SQL Server, where whatever reads from that database gets them without querying the warehouse.

Fresh analytics without loading windows

Because changes stream continuously, analysts query current data instead of waiting for last night's load.

Offload heavy reads

Point analytical queries at the synced copy in MotherDuck and keep SQL Server focused on its operational workload.

What you can sync between MotherDuck 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.

MotherDuck objects SQL Server objects
Tables The main landing target for synced records and source for analysis. Columns Field-level mapping targets with T-SQL types.
Views Modeled projections used as outbound sync sources. Primary and Unique Keys Match keys for idempotent upserts and conflict handling.
Database Shares Read-only copies of a database shared with other users or teams. CDC Change Tables System-populated tables holding captured inserts, updates, and deletes for consumers.
Attached Local DuckDB Databases Local files attached alongside cloud databases for hybrid queries. Stored Procedures T-SQL logic that can validate or post-process synced rows.
Databases Cloud-hosted DuckDB databases that scope a sync's reads and writes. Databases Instance-level databases that scope a sync's reads and writes.
Schemas Namespaces within a database used to organize synced tables. Schemas Namespaces (dbo and custom) used to organize synced tables.
What ships with MotherDuck ⇄ SQL Server

Connect MotherDuck and SQL Server for flexible, real-time data sync.

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

Real-time

Two-way sync

Changes in MotherDuck or SQL Server instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever MotherDuck 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 MotherDuck or SQL Server record.

Observability

Monitoring

Track your MotherDuck ⇄ 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 MotherDuck and SQL Server.

How the MotherDuck and SQL Server connectors work

MotherDuck

Integration surface
SQL through DuckDB clients and drivers using a MotherDuck (md:) connection
Authentication
Access token created in MotherDuck (Settings > General > Create Token), pasted into Stacksync; database name and schema configurable if not using defaults
Change detection
Polling; no log-based CDC or webhook surface is exposed
Capabilities
read · write
Rate limits
Subject to the platform's compute and concurrency limits rather than per-request API rate limits
MotherDuck setup guide

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 MotherDuck 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 MotherDuck 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
    MotherDuck connected
    SQL Server connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the MotherDuck 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 · MotherDuck ⇄ 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
    MotherDuck SQL Server
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

MotherDuck 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.

Learn more about security
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:

OAuth 2 SSH Tunnelling SSL certificates IP Whitelisting VPN gateway VPC peering and more

Related integrations

Every pair below is a real-time, two-way sync. Search all 386 integrations available for MotherDuck and SQL Server.

Popular · 8 of 386
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