Why Waiting on Data Is Costing You
In today's fast-moving digital landscape, timely access to accurate data is the edge your business needs. Whether you're overseeing operations, driving strategy, or delivering value to customers, delays in accessing key business metrics can result in missed opportunities, poor forecasting, and reactive decision-making.
Change Data Capture (CDC) is a powerful yet low-impact technology built into SQL Server and Azure SQL Managed Instance that helps you break free from lagging data. It allows changes in your business systems—like sales, customer updates, or inventory adjustments—to instantly flow into your reporting tools, dashboards, and integrations.
Unlock a Time Machine for Your Business Data
Imagine having a time machine for your business data — that’s exactly what modern temporal tables offer. They automatically capture every change to your records, creating a full historical log that shows how your data looked at any point in time. Whether it's customer profiles, contract terms, or pricing updates, this visibility is invaluable for auditing, compliance, and tracking changes over time.
Best of all, it happens silently in the background with zero disruption to your operations.
When paired with Change Data Capture (CDC), you get a complete picture of data evolution: temporal tables provide the "what and when", while CDC captures the "who and how". Together, they offer unmatched transparency and control — helping you make better decisions and stay ahead of compliance requirements.

Real-Time Data, Real-World Impact
Know immediately when a customer record is updated, a sale is made, or inventory drops below threshold. With CDC in place, these insights can flow instantly into your decision-making tools, enabling more responsive customer service, improved operational efficiency, and proactive business planning.
Imagine this:
- Your sales dashboards update as soon as a deal closes
- Your customer database syncs automatically across platforms
- Your finance team runs reports on live data, not yesterday’s exports
All this without disrupting your existing systems or launching costly digital transformation projects.
That’s the promise of Change Data Capture (CDC). At Assemblysoft, we specialize in implementing it strategically—ensuring it fits your organization’s pace, priorities, and platform, whether that’s on-prem SQL Server or the Azure cloud.
At Assemblysoft, we help you unlock these capabilities without risk. Our UK-based team specializes in aligning CDC strategies with your business goals—whether you're modernizing a legacy ERP system or integrating with third-party platforms.
What Is CDC, in Simple Terms?
Change Data Capture (CDC) is a method of tracking changes made to your data—such as inserts, updates, and deletes—in real time. Rather than constantly querying entire tables to see what's changed, CDC monitors your SQL Server's transaction log behind the scenes and stores just the changes in a special structure.
These tracked changes can then be used to sync systems, update reports, or power real-time apps—all without rewriting or redeploying your existing software.
Think of CDC as a smart data mirror—it only reflects what’s changed, helping your team act on fresh insights faster.
Business Benefits of CDC
CDC Helps Delayed Reports Automatically feed data into dashboards like Power BI or Excel in near real-time Manual Syncing Eliminate spreadsheets or overnight batch jobs for syncing data across systems Compliance & Auditing Capture every change to sensitive data for full traceability Modernization Without Risk
Start using real-time data without replacing your current systems
Assemblysoft’s CDC Enablement Services
We guide businesses through every stage of adopting CDC—tailored to your environment and goals.
🔧 Assessment – We evaluate your current SQL Server (on-prem or cloud) for CDC readiness
🚀 Implementation – We enable CDC on your databases and help configure safe, secure pipelines
🧩 Integration – We connect your change-tracked data into your BI tools, ETL jobs, or custom apps
🛡️ Monitoring & Support – We help set up job monitoring and retention policies for ongoing reliability
Whether you’re running SQL Server 2016+ on-prem or Azure SQL Managed Instance, our UK-based team ensures a seamless transition to real-time operations.
Under the Hood: How CDC Works (For Technical Teams)
Data flow
The following illustration shows the principal data flow for change data capture.
The source of change data for change data capture is the SQL Server transaction log. As inserts, updates, and deletes are applied to tracked source tables, entries that describe those changes are added to the log. The log serves as input to the capture process. Then, it reads the log and adds information about changes to the tracked table's associated change table. Functions are provided to enumerate the changes that appear in the change tables over a specified range, returning the information in the form of a filtered result set. The filtered result set is typically used by an application process to update a representation of the source in some external environment.

Once enabled, CDC works by:
Reading the transaction log for INSERT, UPDATE, and DELETE operations
Populating change tables that mirror your original tables, but include metadata (timestamp, operation type, etc.)
Exposing SQL functions that developers or ETL tools can call to query what’s changed over a specific time window
Each tracked table becomes a "capture instance" with its own change table and functions like:
fn_cdc_get_all_changes_<table>
– all changes between LSNs
fn_cdc_get_net_changes_<table>
– net result of changes per row (optional)
Feature Comparison Table
Feature / Capability | On-Prem SQL Server | Azure SQL Managed Instance |
---|---|---|
Supports Change Data Capture (CDC) | ✅ | ✅ |
Uses SQL Server Agent for CDC | ✅ | ✅ |
Change data stored in separate CDC tables | ✅ | ✅ |
Incremental ETL support via built-in CDC functions | ✅ | ✅ |
Dual capture instances per table (schema evolution) | ✅ | ✅ |
Net change detection with fn_cdc_get_net_changes_* |
✅ | ✅ |
Schema change handling with cdc.ddl_history |
✅ | ✅ |
Compatible with legacy on-prem applications | ✅ | 🔲 (Not applicable) |
Integrated with Azure Data Factory & Synapse | 🔲 (Requires setup) | ✅ |
Azure scalability and HA by default | 🔲 (Manual setup) | ✅ |
Native support for cloud-first modernization | 🔲 (Requires hybrid setup) | ✅ |
🕒 Retention and Cleanup
CDC keeps changes by default for 3 days using a cleanup job that runs nightly. This can be configured to align with your storage, performance, and compliance needs.
🔄 Multiple Schema Versions
CDC can track schema changes and support two capture instances per table, allowing old systems and new systems to run in parallel during transitions.
⚙️ Minimal Overhead
Since CDC reads from the log, it avoids impacting your day-to-day operations. SQL Server Agent must be enabled to support the capture and cleanup processes.
Better Decisions Without Rebuilding Your Systems
Rather than replacing your core systems—which can be risky and expensive—CDC enables incremental modernization. It works with your existing SQL Server or Azure SQL databases to feed downstream systems such as Power BI, Salesforce, or custom dashboards, without touching your application code.
A Strategic Enabler for Digital Transformation
For business leaders, the real power of CDC lies in its ability to future-proof your data strategy. It enables your systems to work together in real time without duplication or disruption. As part of your modernization journey, CDC becomes a stepping stone to cloud adoption, automation, and real-time business intelligence.
Ready to Unlock the Power of Change?
At Assemblysoft, we believe in smart, sustainable modernization. CDC is just one of the many technologies we use to help our clients extract more value from their data, systems, and people.
🔍 Whether you're planning a move to Azure or improving your on-prem SQL Server environment, we can help implement CDC with confidence, clarity, and measurable results.
👉 Get in touch with our team today for a free consultation and see how CDC can transform the way your business sees and uses data.
By introducing CDC:
- Your legacy systems gain new life, becoming real-time data sources
- Your data becomes an asset, always fresh, always available
- Your decisions become proactive, not reactive
And the best part? You don’t need to rebuild your architecture to get started.
Conclusion
In today's competitive landscape, access to up-to-date information is no longer a luxury—it's a necessity. Business owners often face delays in getting accurate data into reporting tools, CRMs, or compliance dashboards. Change Data Capture (CDC) solves this by ensuring that data changes are automatically tracked and delivered in near real-time, giving decision-makers a live view of the business.
Whether you're running operations on-premises or in the cloud with Azure, CDC enables fast, accurate data movement between systems without disrupting day-to-day activities. That means more timely reporting, better forecasting, and faster reactions to emerging trends or risks.