Product News

Sync data 100x faster on Snowflake with Census Live Syncs

Sean Lynch
Sean Lynch March 27, 2024

Sean is co-founder and Chief Product Officer (CPO) at Census. He loves enabling data-driven organizations, so he's energized by introducing the world to Data Activation. San Francisco, California, United States

For years, working with high-quality data in real time was an elusive goal for data teams. Two hurdles blocked real-time data activation on Snowflake from becoming a reality: 

  1. Lack of low-latency data flows and transformation pipelines
  2. The compute cost of running queries at high frequency in order to provide real-time insights

Today, we’re solving both of those challenges by partnering with Snowflake to support our real-time Live Syncs, which can be 100 times faster and 100 times cheaper to operate than traditional Reverse ETL. You can create a Live Sync using any Snowflake table (including Dynamic Tables) as a source, and sync data to over 200 business tools within seconds.

We’re proud to offer the fastest Reverse ETL platform on the planet, and the only one capable of real-time activation with Snowflake.

👉 Luke Ambrosetti discusses Live Sync architecture in-depth on Snowflake’s Medium blog here

Real-Time Composable CDP with Snowflake

Developed alongside Snowflake’s product team, we’re excited to enable the fastest-ever data activation on Snowflake. Today marks a massive paradigm shift in how quickly companies can leverage their first-party data to stay ahead of their competition.

In the past, businesses had to implement their real-time use cases outside their Data Cloud by building a separate fast path, through hosted custom infrastructure and event buses, or piles of if-this-then-that no-code hacks — all with painful limitations such as lack of scalability, data silos, and low adaptability. Census Live Syncs were born to tear down the latency barrier that previously prevented companies from centralizing these integrations with all of their others.

Census Live Syncs and Snowflake now combine to offer real-time CDP capabilities without having to abandon the Data Cloud. This Composable CDP approach transforms the Data Cloud infrastructure that companies already have into an engine that drives business growth and revenue, delivering huge cost savings and data-driven decisions without complex engineering. 

Together we’re enabling marketing and business teams to interact with customers at the moment of intent, deliver the most personalized recommendations, and update AI models with the freshest insights.

Doing the Math: 100x Faster and 100x Cheaper

There are two primary ways to use Census Live Syncs — through Snowflake Dynamic Tables, or directly through Snowflake Streams. 

  • Near real time: Dynamic Tables have a target lag of minimum 1 minute (as of March 2024).
  • Real time: Live Syncs can operate off a Snowflake Stream directly to achieve true real-time activation in single-digit seconds.

Using a real-world example, one of our customers was looking for real-time activation to personalize in-app content immediately. They replaced their previous hourly process with Census Live Syncs, achieving an end-to-end latency of <1 minute.

They observed that Live Syncs are 144 times cheaper and 150 times faster than their previous Reverse ETL process. It’s rare to offer customers multiple orders of magnitude of improvement as part of a product release, but we did the math.

Continuous Syncs (traditional Reverse ETL)Census Live SyncsImprovement
Cost24 hours = 24 Snowflake credits. 24 * $2 * 30 = $1440/month⅙ of a credit per day. ⅙ * $2 * 30 = $10/month144x
SpeedTransformation hourly job + 15 minutes for ETL = 75 minutes on average30 seconds on average150x


The previous method of lowest latency Reverse ETL, called Continuous Syncs, required a Snowflake compute platform to be live 24/7 in order to continuously detect changes. This was expensive and also wasteful for datasets that don’t change often.

Assuming that one Snowflake credit is on average $2, traditional Reverse ETL costs 24 credits * $2 * 30 days = $1440 per month.

Using Snowflake’s Streams to detect changes offers a huge saving in credits to detect changes, just 1/6th of a single credit in equivalent cost, lowering the cost to $10 per month.


Real-time activation also requires ETL and transformation workflows to be low latency. In this example, our customer needed real-time activation of an event that occurs 10 times per day. First, we reduced their ETL processing time to 1 second with our HTTP Request source. On the activation side, Live Syncs activate data with subsecond latency.

1 second HTTP Live Sync + 1 minute Dynamic Table refresh + 1 second Census Snowflake Live Sync = 1 minute end-to-end latency. This process can be even faster when using Live Syncs with a Snowflake Stream.

For this customer, using Census Live Syncs on Snowflake was 144x cheaper and 150x faster than their previous Reverse ETL process

How Live Syncs work

It’s easy to set up a real-time workflow with Snowflake as a source in three steps:

  1. Create a sync with a Snowflake Table or Dynamic Table as the source. Make it Live.
  2. Census automatically creates a Snowflake Stream on top of the selected source object.
  3. The Stream allows us to detect new data quickly and cheaply. As soon as we receive the signal, we query the new data and push it to the destination instantly.
    1. For Snowflake Tables, we immediately sync data to the destination in single-digit seconds.
    2. Snowflake Dynamic Tables have a minimum of 1-minute latency, which we expect to decrease over time.

Set up a Census Live Sync on a Snowflake table or Dynamic Table, and Census automatically creates a Snowflake Stream for you


Over 9,000 modern enterprises use the Snowflake Data Cloud as their single source of truth. At Census, we recognized a gap in how data was being used for real-time use cases, and we set out to fill it. We’ve always believed that Snowflake should be the source of truth for business action, but warehouse-based architecture (until now) wasn’t capable of activation in single-digit seconds.

Together, our goal is to revolutionize how business teams can immediately harness and act upon their data, unlocking new high-speed use cases like geotargeted campaigns, abandoned cart notifications, and lead routing in any business tool. 

Live Syncs on Snowflake are available today. Get a product onboarding or start a free 14-day trial now.