# Watermarkless Change Data Capture (CDC) for SQL Server in Estuary

Estuary now supports Watermarkless Change Data Capture (CDC) for SQL Server, enabling real-time data movement without the need for watermark writes.

## What’s New?

With this update, Estuary now supports CDC from SQL Server without the need for watermark writes. This new functionality exists alongside the traditional watermark-based mechanism, giving you the flexibility to choose the best fit for your environment.

## Why This Matters

- **Truly Watermarkless CDC:** Eliminate the need for watermark tables and avoid any writes to the source database. This minimizes operational overhead and reduces security concerns related to write permissions.

- **Simplified Permissions:** The new implementation only requires `VIEW DATABASE STATE` permission (or `VIEW DATABASE PERFORMANCE STATE` for SQL Server 2022+), making setup easier in read-only or restricted environments.

- **Seamless Transition:** Existing captures continue to work with watermark-based CDC. New captures can opt into the watermarkless mode by adding the `read_only` feature flag in the advanced endpoint configuration.

## How to Enable

- **For New Captures:** Add the `read_only` feature flag in your advanced endpoint config to enable watermarkless CDC.

- **For Existing Captures:** No changes are required immediately. We plan to flip the default behavior after further testing, but you'll always have the option to opt in or out as needed using `read_only` or `no_read_only` feature flags.

## Get Started Today

Ready to simplify your SQL Server CDC workflows? Head over to Estuary, set up your capture with the `read_only` flag, and experience the benefits of watermarkless CDC.

For detailed documentation, visit [Estuary Docs](https://docs.estuary.dev/).

Stay tuned for more updates as we continue to evolve Estuary!