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<h2>Machine Learning with Snowflake ML</h2>Snowflake ML is a machine learning framework built directly into the Snowflake platform. It allows users to build, train, and deploy ML models using both SQL and Python, all without needing to move data outside the Snowflake environment. This tight integration reduces data transfer overhead, improves security, and accelerates the overall ML workflow. With Snowflake ML, teams can handle everything—from data preparation and feature engineering to model training and inference—within a single, unified platform.Let’s explore how we can integrate ML into our current workflow!<h3>What is Snowflake ML?</h3><ul><li>Snowflake ML is an integrated suite of features and tools for building and deploying machine learning models directly within Snowflake’s data platform.</li><li>It combines:<ul><li>In-database ML functions (like ML.PREDICT)</li><li>Python-based ML workflows using Snowpark for Python</li><li>Integration with external frameworks (like scikit-learn, XGBoost, etc.)</li></ul></li><li>It allows data engineers and data scientists to work with ML models where the data lives, avoiding data movement and reducing complexity.</li></ul><h3>Benefits of Snowflake ML</h3><ul><li>Simplifies ML workflows by using familiar SQL and Python.</li><li>Eliminates data movement, which can introduce latency and security risks.</li><li>Use Snowflake’s scalability to handle large datasets.</li><li>Supports MLOps practices, making it easier to deploy and monitor models in production.</li></ul><h3>How Snowflake ML Works: Step by Step</h3><ul><li>Data Preparation with Snowflake<ul><li>Use Snowflake’s SQL and Snowpark DataFrame APIs to:<ul><li>Clean data (handle missing values, outliers)</li><li>Join data from multiple tables</li><li>Create training and test datasets</li></ul></li></ul></li></ul>Example:<figure id="figure-85mn19mf49mbcjztjz"><img id="85mn19mf49mbcjztjz" src="https://cdn.durable.co/blocks/32JXUZZ0Vg6BCtFsBeERHdrhD3pEO4jGycoh9K49nnU7CZFWbgT4NBv5bYvMP6O4.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/32JXUZZ0Vg6BCtFsBeERHdrhD3pEO4jGycoh9K49nnU7CZFWbgT4NBv5bYvMP6O4.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>Feature Engineering with Snowpark for Python<ul><li>Use Snowpark’s Python API for advanced transformations: </li></ul></li></ul><figure id="figure-aix8i2yikrmbck1c4r"><img id="aix8i2yikrmbck1c4r" src="https://cdn.durable.co/blocks/3aQiwy1kRnOQAtbMKwHFRN8MSSz8lrHRynFPDfnmjn1mfmvtqUosd9k0nv4cgTy5.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/3aQiwy1kRnOQAtbMKwHFRN8MSSz8lrHRynFPDfnmjn1mfmvtqUosd9k0nv4cgTy5.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>Model Training: In-Snowflake or External<ul><li>Option A: In-Snowflake ML Functions<ul><li>Use Snowflake ML functions to train models in SQL. </li></ul></li></ul></li></ul><figure id="figure-npujv8oakmbck20du"><img id="npujv8oakmbck20du" src="https://cdn.durable.co/blocks/fGmzx1ZrMXMhpN4kXAEk05HalbOm5KEkjbxaHECy4lsKnKsNx6T0bNHViGVy3exc.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/fGmzx1ZrMXMhpN4kXAEk05HalbOm5KEkjbxaHECy4lsKnKsNx6T0bNHViGVy3exc.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li style="list-style-type: none;" data-mce-style="list-style-type: none;"><ul><li>Option B: Snowpark for Python + External Libraries<ul><li>Use Snowpark’s Python API to load data into pandas and train models with scikit-learn. </li></ul></li></ul></li></ul><figure id="figure-72fm3hnoc8mbck4jac"><img id="72fm3hnoc8mbck4jac" src="https://cdn.durable.co/blocks/19i4wTJeg4UfsDNE6I503uDubhxU63YgeaPu8EpJUaTGrSGctvWBmXuoOzff9qfW.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/19i4wTJeg4UfsDNE6I503uDubhxU63YgeaPu8EpJUaTGrSGctvWBmXuoOzff9qfW.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>Model Deployment and Prediction<ul><li>Using In-Snowflake ML for predictions:</li></ul></li></ul><figure id="figure-n8dorkt4cmmbck5s1l"><img id="n8dorkt4cmmbck5s1l" src="https://cdn.durable.co/blocks/19N77y3TaCM63wtdTzqtmU2ilsPPRgimzWLrSkC72VS1WTU09NDT2Jug2HIt3evI.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/19N77y3TaCM63wtdTzqtmU2ilsPPRgimzWLrSkC72VS1WTU09NDT2Jug2HIt3evI.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li style="list-style-type: none;" data-mce-style="list-style-type: none;"><ul><li>Using Python UDFs for external models: </li></ul></li></ul><figure id="figure-pypjmhr4bfmbck7l68"><img id="pypjmhr4bfmbck7l68" src="https://cdn.durable.co/blocks/319BXQQCzvIezHfrYAMRefjPJJtdSVEDSpbz6MESDzganxyfYFUMWMyIldVFKWWr.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/319BXQQCzvIezHfrYAMRefjPJJtdSVEDSpbz6MESDzganxyfYFUMWMyIldVFKWWr.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>Monitoring and Retraining<ul><li>Use Snowflake’s Task feature to schedule model retraining.</li><li>Monitor performance using:<ul><li>Model evaluation metrics</li><li>Regular validation on fresh data</li></ul></li></ul></li></ul><h3>Real-Life Example: Predicting Customer Churn</h3>Let’s say we’re a SaaS company using Snowflake to manage customer data. We want to predict which customers are likely to churn based on usage patterns.<ul><li>Step 1: Clean and join usage logs and customer profiles in Snowflake.</li><li>Step 2: Use Snowpark to create features like:<ul><li>Average monthly login counts</li><li>Number of support tickets</li></ul></li><li>Step 3: Train a classification model (e.g., logistic regression) using Snowpark for Python.</li><li>Step 4: Deploy the model with a UDF, running predictions in Snowflake.</li><li>Step 5: Use the predictions to trigger proactive retention campaigns. </li></ul><figure id="figure-neisyuk07mbck8cuu"><img id="neisyuk07mbck8cuu" src="https://cdn.durable.co/blocks/0qt3EvG5a5aXpFXwNndcWD2luqnE8ZwSVFEhOmeYz1aOEFARPeYdmLkLDH3WB3yO.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/0qt3EvG5a5aXpFXwNndcWD2luqnE8ZwSVFEhOmeYz1aOEFARPeYdmLkLDH3WB3yO.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>OUTPUT :&nbsp;Accuracy: 0.85<h3>Key Benefits&nbsp;</h3><ul><li>No data movement: Models run where the data lives.</li><li>Unified environment: Use SQL and Python together.</li><li>Faster deployment: Skip the hassle of moving data to external ML platforms.</li><li>Scalability: Use Snowflake’s compute power to train models on large datasets.</li></ul><h3>Best Practices with Snowflake ML</h3><ul><li>Start with small prototypes using sample data to validate your approach.</li><li>Use Snowflake’s built-in ML functions for simpler use cases.</li><li>Switch to external libraries for more advanced models, using Python UDFs.</li><li>Monitor model performance regularly and retrain as needed.</li><li>Collaborate across teams—data engineers, analysts, and scientists—to get the most out of our data. </li></ul>

Machine Learning with Snowflake ML

<h2>Building Real-Time Data Pipelines with Snowpipe Streaming: Architecture, Implementation, and Pitfalls </h2>Real-time analytics is becoming essential as businesses demand fresh data for quicker insights. Modern use cases – from IoT sensor monitoring to clickstream analysis and security log auditing often require data to arrive in Snowflake within seconds of occurrence.Traditional batch or file-based ingestion introduces minutes of delay, which can miss these time-sensitive events. Snowpipe Streaming is Snowflake’s low-latency ingestion API designed exactly for these scenarios. Unlike classic Snowpipe, which loads files from cloud storage, Snowpipe Streaming lets us push rows directly into Snowflake tables via an SDK. This cuts out the staging step and dramatically reduces load latency.<h3>What Is Snowpipe Streaming?</h3>Snowpipe Streaming is Snowflake’s native solution for low-latency data ingestion. Unlike traditional batch loading or standard Snowpipe (which uploads files to S3/GCS before ingestion), Snowpipe Streaming uses an API-based approach to send rows directly into a Snowflake table from your application.This approach is built for situations where:<ul><li>We need data to show up in dashboards within seconds.</li><li>Data comes in continuously, not in batches.</li><li>We want to skip intermediate storage like files.</li></ul><h3>How It Differs from Regular Snowpipe</h3><table style="border-collapse: collapse; width: 100%;" border="1" data-mce-style="border-collapse: collapse; width: 100%;"><tbody><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">FEATURE</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">TRADITIONAL SNOWPIPE</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">SNOWPIPE STREAMING</td></tr><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Input Format&nbsp;</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Files (CSV , JSON , Parquet)&nbsp;</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">Rows via API</td></tr><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Latency</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Minutes</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">Seconds</td></tr><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Staging Layer</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Required (S3 , GCS)</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">Not required</td></tr><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Retry and Failover</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Managed by Snowflake</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">Managed by client&nbsp;</td></tr><tr><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Transformations</td><td style="width: 33.3325%;" data-mce-style="width: 33.3325%;">Needs extra setup</td><td style="width: 33.335%;" data-mce-style="width: 33.335%;">Combine with Streams &amp; Tasks</td></tr></tbody></table><h3>Why It Matters</h3>Let’s say we run a logistics platform. Orders come in continuously, and customers want real-time updates. With Snowpipe Streaming, we can:<ul><li>Stream order data directly into Snowflake.</li><li>Trigger warehouse inventory updates in near real-time.</li><li>Alert teams instantly if something goes wrong.</li><li>This lets us move from hourly reports to live views with minimal infrastructure.</li></ul><h3>Architecture: How Snowpipe Streaming Works</h3>Snowpipe Streaming is based on a client-server model. Our application uses Snowflake’s Java SDK to open a channel and push rows directly into a Snowflake table.Key Concepts:<ul><li>Channel: A virtual pipe to send records to a specific table. Each channel handles inserts and tracks progress using offset tokens.</li><li>Offset Token: A user-defined string that tracks how far the application has ingested data. Useful for error recovery.</li><li>Flush: The SDK batches and flushes rows to Snowflake. You can trigger it manually or let it flush automatically. </li></ul><figure id="figure-15p9xm22vsmbckn4ml"><img id="15p9xm22vsmbckn4ml" src="https://cdn.durable.co/blocks/37YrHOWonHOZs2hE3YGnzAwwLfV45mVkMpicSOvk2efSZvNfuPWR843NhMqVn5LF.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/37YrHOWonHOZs2hE3YGnzAwwLfV45mVkMpicSOvk2efSZvNfuPWR843NhMqVn5LF.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>The SDK opens an HTTPS connection to Snowflake.</li><li>Data is sent in batches over the channel.</li><li>Snowflake ingests rows, commits the batch, and makes them available for query.</li><li>If there’s a failure, we use the offset token to retry just the missing data. </li></ul><h3>Step-by-Step Implementation</h3>Let’s walk through how to build a basic streaming pipeline using Snowpipe Streaming.<ol><li>Set Up a Target Table in Snowflake<ul><li><figure id="figure-hlydbo8o8mbckosx2"><img id="hlydbo8o8mbckosx2" src="https://cdn.durable.co/blocks/dzQ7SiDfPGEtVuYcfdxEnq697S9ErtsgtKaIEQWr9yQeOGMXBb15oa5e2A3IjevV.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/dzQ7SiDfPGEtVuYcfdxEnq697S9ErtsgtKaIEQWr9yQeOGMXBb15oa5e2A3IjevV.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Add the Java SDK<ul><li>Snowpipe Streaming currently works only with Java. Add the SDK to your project:</li><li><figure id="figure-h5p4pop6jfmbckpfr3"><img id="h5p4pop6jfmbckpfr3" src="https://cdn.durable.co/blocks/156gzVpxzkSDFQw5H7TqrIb3x6ueFlo8xkCtFNoa8IqtC7yXjVWff2UkmWxPMoEd.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/156gzVpxzkSDFQw5H7TqrIb3x6ueFlo8xkCtFNoa8IqtC7yXjVWff2UkmWxPMoEd.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Connect to Snowflake<ul><li><figure id="figure-ny9we091jmbckrr87"><img id="ny9we091jmbckrr87" src="https://cdn.durable.co/blocks/1cG5uLPC2ICBqxnNl9xTaga29Kl4j5O6y3jJWtz4qmvlUEQkOFQlb9ysAhFceT7U.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/1cG5uLPC2ICBqxnNl9xTaga29Kl4j5O6y3jJWtz4qmvlUEQkOFQlb9ysAhFceT7U.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Open a Channel <ul><li><figure id="figure-i6iycx38hlmbcktpiz"><img id="i6iycx38hlmbcktpiz" src="https://cdn.durable.co/blocks/39XZimQdiZcGHk2Pub9shyQzXK7G9vRsAIxBpOOo43DFiUr9kYAH6s7SlWm5KpRT.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/39XZimQdiZcGHk2Pub9shyQzXK7G9vRsAIxBpOOo43DFiUr9kYAH6s7SlWm5KpRT.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Prepare and Send Rows <ul><li><figure id="figure-wvzj3c07ambckvcki"><img id="wvzj3c07ambckvcki" src="https://cdn.durable.co/blocks/12v1qEi9ovBSOve2rk6VW8vbr7XZxhuMlrocNbPlY9lwAMVYfilB7usdTzosLuNM.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/12v1qEi9ovBSOve2rk6VW8vbr7XZxhuMlrocNbPlY9lwAMVYfilB7usdTzosLuNM.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Handle Errors and Retry<ul><li>Store offset tokens so you can resume from the last successful insert. This is your responsibility—the SDK won’t do it for you.</li></ul></li></ol><h3>Real-Life Use Case: Real-Time Fraud Detection</h3>Suppose we are working with a fintech platform that needs to detect suspicious activity within 10 seconds of a transaction. Waiting for nightly loads isn’t viable.Here’s how Snowpipe Streaming helps:<ul><li>The application pushed transaction events to a Java service.</li><li>The service used Snowpipe Streaming to insert data into a Snowflake table.</li><li>A Stream and Task setup evaluated transactions in real-time.</li><li>Suspicious patterns triggered alerts within seconds.</li></ul>This setup reduced fraud detection time from hours to under 10 seconds—without maintaining a Kafka pipeline or real-time ETL platform.<h3>Combining with Streams and Tasks</h3>Snowpipe Streaming handles the ingestion. For downstream logic (like filtering, enrichment, or aggregation), we can use Streams and Tasks.<figure id="figure-54qy3mcymbmbcl07nf"><img id="54qy3mcymbmbcl07nf" src="https://cdn.durable.co/blocks/6BCmQXWrxkJy6dTbCjJypJQBLMCAnfEMOYPVARinEpwd2duhgEUb0FboLklQI5KT.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/6BCmQXWrxkJy6dTbCjJypJQBLMCAnfEMOYPVARinEpwd2duhgEUb0FboLklQI5KT.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><h3>Monitoring and Observability</h3>While Snowpipe Streaming is lightweight, we still need visibility into:<ul><li>How many rows are ingested per second</li><li>Whether inserts are successful</li><li>Where failures occur</li></ul>Snowflake does not yet provide built-in dashboards for streaming inserts, but we can use:<ul><li>Custom logs in the Java app</li><li>Offset token checkpoints</li><li>Metadata queries to count rows ingested over time</li></ul><h3>Pitfalls and How to Avoid Them</h3><ol><li>Only Java Is Supported&nbsp;<ul><li>If our stack is Python, Node.js, or Go, we’ll need to introduce a Java service just for streaming.<ul><li>Workaround: Keep this ingestion logic isolated and containerized. Treat it as a simple microservice that just moves data.</li></ul></li></ul></li><li>Manual Retry Logic<ul><li>The SDK doesn’t retry failed inserts automatically. If the connection fails midway, those rows are lost unless you catch the error and resend.<ul><li>Tip: Log every offset token and error. Retry only the failed batch.</li></ul></li></ul></li><li>Small Row Inserts Are Expensive<ul><li>Every insert has overhead. If you insert one row at a time, costs will add up.<ul><li>Best practice: Batch rows (e.g., 100–500 at a time) before sending them.</li></ul></li></ul></li><li>No Built-in Alerting<ul><li>Snowpipe Streaming doesn’t notify us if ingestion stalls or fails.<ul><li>Suggestion: Build basic health checks. Monitor:<ul><li>Time since last successful insert</li><li>Size of incoming queue vs outgoing inserts</li></ul></li></ul></li></ul></li><li>Channel Throughput Has Limits<ul><li>Each channel supports limited concurrency and throughput. High-frequency apps may hit bottlenecks.<ul><li>Fix: Create multiple channels and use a round-robin strategy in your client.</li></ul></li></ul></li></ol><figure id="figure-kvvlmffbdmbclefbb"><img id="kvvlmffbdmbclefbb" src="https://cdn.durable.co/blocks/4TbnlegiAU9Xa0A7EyO2pd7lMK28WgxFtfu0ILSRIFVwtXTYtAHIAB4wg2djWZfA.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionX="undefined" data-positionY="undefined" data-fullWidth="false"/></figure>Snowpipe Streaming fills a critical gap: it helps us get real-time data into Snowflake without managing batch jobs or message queues.But it comes with trade-offs:<ul><li>We must handle retries and monitoring ourselves.</li><li>It only works with Java for now.</li><li>Costs can rise if we don’t batch efficiently.</li></ul>Used wisely, it’s a powerful addition to any real-time data pipeline—especially when paired with Streams and Tasks.

Real-Time Data Pipelines with Snowpipe Streaming

<h2>Designing Scalable ELT Pipelines with Snowpipe, Streams, and Tasks</h2>Snowflake provides built‑in features to automate ELT (extract, load, transform) pipelines. Snowpipe continuously loads new data files from cloud storage into a Snowflake table. Streams track the “delta” of data – they capture exactly which rows were inserted, updated, or deleted in a table since the last time checked. Tasks run SQL code on a schedule or when triggered by an event. By combining these, we can set up a pipeline that automatically ingests data, detects new rows, and processes them without manual intervention. For example, Snowpipe ingests new files as they arrive, a stream on the raw table records those new rows, and a task can be set to run SQL to transform or move those rows into a final table.<h3>Snowpipe: Continuous Ingestion</h3>Snowpipe is Snowflake’s automated, serverless loading service. When we create a pipe object, we give it a COPY statement that points to a cloud stage (e.g. S3, GCS, or Azure) and a target table. Snowpipe then auto-ingests new files. we can trigger it via cloud event notifications or API calls. In practice, Snowpipe loads data from arriving files in small batches, making it available within minutes. For example:<figure id="figure-3xlg6feuymmbb3ud3a"><img id="3xlg6feuymmbb3ud3a" src="https://cdn.durable.co/blocks/36wQJjI0UiHdzXo86hxyPknvkO9vCP7CNYfB8uAbMRYmtOM4eP3YaeKkcL3Z1tIv.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/36wQJjI0UiHdzXo86hxyPknvkO9vCP7CNYfB8uAbMRYmtOM4eP3YaeKkcL3Z1tIv.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Here my_pipe will watch the @my_stage location and automatically load each new file into raw_table. Snowpipe handles the compute behind the scenes (it is serverless), so we don’t need to manage any loading servers. This lets the pipeline scale: even if many files arrive, Snowpipe will queue and load them in parallel using Snowflake’s managed resources.<h3>Streams: Capturing Changes</h3>A stream in Snowflake tracks row-level changes in a table. Technically, a stream object “records the delta of change data capture (CDC) information” for its source table. In simpler terms, once we have a table that Snowpipe is loading into (say raw_table), we create a stream on it:<figure id="figure-xho8lx851xmbb3x8ha"><img id="xho8lx851xmbb3x8ha" src="https://cdn.durable.co/blocks/7UzBecI8MAKfHLKA9oTUpIOjKR2IBaxhKEI4XNtROi2ZyFYdMT1GKa8K7MiLo95N.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/7UzBecI8MAKfHLKA9oTUpIOjKR2IBaxhKEI4XNtROi2ZyFYdMT1GKa8K7MiLo95N.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>This raw_stream will see every row that’s inserted into raw_table. When you query the stream, it returns exactly the new (or changed) rows since the last read. This means our pipeline only processes new data, not the entire table. Streams make incremental ELT easy: downstream tasks can read from the stream and automatically pick up only the new inserts or updates. (Under the hood, Snowflake remembers how far each stream has been consumed so it can present just the next set of changes.)<h3>Tasks: Automated Transformations</h3>A task is a Snowflake object that runs a SQL statement on a schedule or when triggered. We can create a task to perform transformations, upserts, or other business logic. For example, a task might merge data from the raw stream into a dimension table. Tasks can be defined with a CRON schedule, or with a WHEN clause to watch a stream. For instance:<figure id="figure-fexkikx6rembb3zxzc"><img id="fexkikx6rembb3zxzc" src="https://cdn.durable.co/blocks/b58jeVVE7kUeAxeDbnpdBSia0zXiI8f5BDbR52kgoyPFsxMqfhggYRLYmKjt85HZ.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/b58jeVVE7kUeAxeDbnpdBSia0zXiI8f5BDbR52kgoyPFsxMqfhggYRLYmKjt85HZ.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>This example task checks raw_stream every minute and only runs the MERGE if raw_stream has new rows. We can also chain tasks (task graphs) so that one task runs after another. Snowflake efficiently skips tasks when there’s no work: “If no data is in the stream, Snowflake skips the run without using compute resources.” In other words, idle tasks don’t waste warehouse time. By using tasks, we can automate the transform step of ELT right inside Snowflake, and we can scale by assigning larger or multi-cluster warehouses as needed.<h3>How They Work Together</h3>The components combine into an automated pipeline. <ul><li>First, put new data files in a cloud stage (for example, an S3 bucket).</li><li>Snowpipe’s pipe watches that stage and loads each file into a raw table as soon as it appears.</li><li>The stream on that raw table captures every new row that Snowpipe inserts.</li><li>A task (or tasks) is set up to run when the stream has data or on a schedule. The task’s SQL reads from the stream and applies whatever transformations or merges are needed into final tables.</li></ul>The diagram below shows a high-level view of this flow:<figure id="figure-s6706bvt44mbb4euxe"><img id="s6706bvt44mbb4euxe" src="https://cdn.durable.co/blocks/2cyJaKHXyQVsLNPchxBijJxBJ4lnhnYEW0eOT26JKCTJ3trWAriOMj0HrmcymPam.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionX="undefined" data-positionY="undefined" data-fullWidth="false"/></figure>Above, new data in cloud storage goes through Snowpipe into Raw Table. The stream watches Raw Table. When new rows appear, the task is triggered to process them into the final table.<h3>Pipeline Setup Steps</h3><ul><li>Set up the stage and pipe. Configure an external stage pointing to your storage and create a Snowpipe pipe. For example:<ul><li><figure id="figure-8635gple38mbb443dt"><img id="8635gple38mbb443dt" src="https://cdn.durable.co/blocks/1b86GQmKeXmK594nB7Q8OtLMzHyMx2mkZawmRNscLThasG1y9FVovxYMqOwPHifX.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/1b86GQmKeXmK594nB7Q8OtLMzHyMx2mkZawmRNscLThasG1y9FVovxYMqOwPHifX.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li><li>This pipe contains the COPY command from @my_stage to raw_table. New files arriving in the stage will auto-ingest into raw_table via Snowpipe.</li></ul></li><li>Create the raw table and stream. Make a table to hold the raw data, then create a stream on it:<ul><li><figure id="figure-udlrlcx4vcmbb45xiz"><img id="udlrlcx4vcmbb45xiz" src="https://cdn.durable.co/blocks/33cSVeMdLoPKVFbQy8kFKqJ6DRgGbZM9MtYws43jPzfbTZjya3tJHgwLC9WBHBDz.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/33cSVeMdLoPKVFbQy8kFKqJ6DRgGbZM9MtYws43jPzfbTZjya3tJHgwLC9WBHBDz.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li><li>The stream will capture all inserted rows in raw_table. (If Snowpipe loads multiple files, the stream accumulates those inserts.)</li></ul></li><li>Define tasks for transformations. For each step we need, we create a task. We can use a time schedule or trigger it when the stream has data. For example:<ul><li><figure id="figure-5g2vsh44fmbb4766g"><img id="5g2vsh44fmbb4766g" src="https://cdn.durable.co/blocks/16zMtC74xAyOiQowk5XmMPfmy8mkRtgAyRTTAuHE08sWS1BpmOfItzoRTk47eXu4.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/16zMtC74xAyOiQowk5XmMPfmy8mkRtgAyRTTAuHE08sWS1BpmOfItzoRTk47eXu4.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li><li>This task runs as soon as new data is in raw_stream, and inserts/merges it into processed_table. If the stream is empty, Snowflake will simply skip the task.Finally, ALTER TASK transform_task RESUME; to activate it.</li></ul></li><li>(Optional) Chain tasks and additional streams. We can create multiple streams on the same raw table if we want parallel pipelines or different data paths. Similarly, tasks can be chained using AFTER clauses or by having one task’s output feed another’s input. This allows building complex, multi-stage pipelines entirely in Snowflake.</li></ul><h3>Best Practices and Tips</h3><ul><li>Use auto-ingest for low latency. Enable AUTO_INGEST=TRUE (and cloud event notifications) so Snowpipe loads files immediately. This minimizes delay from arrival to availability.</li><li>Keep tasks focused. Make tasks do one clear operation (e.g. loading a table or calling a proc). This keeps warehouses from getting too hot and makes it easy to scale out with multiple tasks.</li><li>Idempotent loads. Write your task SQL to handle duplicates or re-runs safely (for example, using MERGE). This way if something retries, it won’t corrupt data.</li><li>Size files appropriately. For Snowpipe, aim for moderate file sizes (tens to hundreds of MB) to balance ingestion speed and overhead. Very tiny files can overwhelm the system with many loads.</li><li>Use multiple streams if needed. If one table feeds different tasks (e.g. splitting data to two targets), create separate streams so each task sees all rows it needs.</li><li>Monitor and scale compute. Assign a warehouse size that matches the workload. Snowflake can use multi-cluster warehouses to handle spikes. Monitor the Task History and Warehouses usage to adjust.</li><li>Handle failures. Use Snowflake’s error handling (like VALIDATION_MODE=RETURN_ERRORS) or task retries. You can also include error logging tables or make tasks call stored procedures with try/catch.</li><li>Suspend tasks if idle. If a pipeline is paused (e.g. no data for a while), you can SUSPEND TASK to save compute. Resume when you expect data.</li><li>Use Streams for CDC. If your sources can send deletes or updates, streams will capture those too. Ensure your tasks handle those cases if needed (e.g. delete rows in target).</li><li>Document your pipeline. Label pipes, streams, and tasks clearly, and comment your SQL. This makes it easier for the team to understand the flow.</li></ul>By following these guidelines, we can build an automated, elastic ELT pipeline in Snowflake. Snowpipe handles ingestion without extra servers, streams lets us process just the new data, and tasks lets us run SQL workflows on demand. Together, they enable data engineers to focus on business logic instead of plumbing, while Snowflake scales the actual work under the hood.

Scalable ELT Pipelines with Snowpipe, Streams, and Tasks

<h2>Data Masking vs Tokenization in Snowflake: Strategies for Sensitive Data</h2>Organizations must protect sensitive data (PII, PHI, PCI, etc.) stored in the Snowflake Data Cloud. Two common approaches are data masking and tokenization, which both hide real data from unauthorized users but work differently.In Snowflake, dynamic data masking uses masking policies applied at query time, while tokenization replaces data with tokens before loading and detokenizes on query via external functions.<h3>Understanding Data Masking</h3>Data masking involves hiding original data by substituting or obfuscating it, ensuring that sensitive information isn't exposed to unauthorized users. In Snowflake, Dynamic Data Masking (DDM) allows for policy-driven transformations of column values at query time, without altering the underlying data.Snowflake masking supports different techniques:<ul><li>Full masking: completely hide a value (e.g. show ** for all non-authorized users).</li><li>Partial masking: reveal only a part (e.g. mask all but last 4 digits of a credit card).</li><li>Pseudonymized masking: replace value with a deterministic surrogate (e.g. SHA2() hash). This keeps identical inputs mapping to the same output, so data can still be aggregated or joined on masked values.</li></ul>Masking policies are schema-level objects applied to table or view columns. At query time, Snowflake automatically rewrites the query and applies the policy everywhere the column appears. Whether the user sees real or masked data depends on conditions in the policy (often based on CURRENT_ROLE() or IS_ROLE_IN_SESSION())<h3>Implementing Data Masking in Snowflake</h3><ol><li>Create a Masking Policy: Define a policy using SQL expressions to specify how data should be masked based on user roles.<ul><li><figure id="figure-mnu6gpa6jtmbb2p2m4"><img id="mnu6gpa6jtmbb2p2m4" src="https://cdn.durable.co/blocks/2dlwIbc8O4N01wOduY8ecZHFv1TtHw6prCqrvo5oq2uJ7Tp0BEfuPO0YeCERaBbk.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/2dlwIbc8O4N01wOduY8ecZHFv1TtHw6prCqrvo5oq2uJ7Tp0BEfuPO0YeCERaBbk.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Apply the Policy to a Column: Use ALTER TABLE to set the masking policy on specific columns.<ul><li><figure id="figure-yqv0vg7l9mbb2pnxu"><img id="yqv0vg7l9mbb2pnxu" src="https://cdn.durable.co/blocks/fruhdlgfbR1LZfINN4PsdQkDJtlYG187jIqwifijETWBCxX06eyrNdSrscD9QRhu.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/fruhdlgfbR1LZfINN4PsdQkDJtlYG187jIqwifijETWBCxX06eyrNdSrscD9QRhu.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Test with Different Roles: Execute queries under various roles to ensure masking behaves as intended.<ul><li><figure id="figure-3ourwzwyt4mbb2rm84"><img id="3ourwzwyt4mbb2rm84" src="https://cdn.durable.co/blocks/24h1up0cJAQovGyEGEdWd3I25a5epi3JKDwHOZdtygf6Zkbn6JIUssO1a1Aab6Z8.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="null" data-positiony="null" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/24h1up0cJAQovGyEGEdWd3I25a5epi3JKDwHOZdtygf6Zkbn6JIUssO1a1Aab6Z8.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li></ol><h3>Use Cases for Data Masking</h3><ul><li>Role-Based Access: Allow analysts to work with production data without exposing sensitive values. (E.g. analysts see only the last 4 of a phone number or SSN, while auditors see the full data.)</li><li>Testing Environments: Provide realistic test data by masking PII in production tables (so testers can run queries without risk).</li><li>Compliance: Meet regulatory requirements by ensuring only authorized roles can view sensitive data. Masking helps show compliance by demonstrating data is hidden in query results.</li><li>Data Sharing: When sharing data externally (e.g. via Snowflake Secure Data Sharing), apply masking policies to protect sensitive fields.</li></ul><figure id="figure-5qdkj3v9lnmbb310be"><img id="5qdkj3v9lnmbb310be" src="https://cdn.durable.co/blocks/3aXuQFuxzu6UxIkEJlZYIZbCdToCTlvwOKSGs0hj790cb1QIUcsjePYlRyVxoF6Q.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/3aXuQFuxzu6UxIkEJlZYIZbCdToCTlvwOKSGs0hj790cb1QIUcsjePYlRyVxoF6Q.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><h3>Understanding Tokenization</h3>Tokenization replaces sensitive data with non-sensitive placeholders (tokens) before storing it in Snowflake. The original data is stored securely outside Snowflake, and authorized users can retrieve it via detokenization processes.Unlike masking, tokenization alters the data at rest. In Snowflake, tokenization is done via external tokenization: data is sent to a token service (or in-house function) that returns tokens, and Snowflake stores those tokens instead of the original values. Original data is kept in a secure token vault or key-management system. At query time, Snowflake can call an external function to detokenize values on the fly (for roles that should see real data).<h3>Implementing Tokenization in Snowflake</h3><ol><li>Set Up a Tokenization Service: Utilize a third-party or custom service to tokenize data before loading it into Snowflake.</li><li>Create an External Function: Define a function in Snowflake that calls the tokenization service to detokenize data when necessary.<ul><li><figure id="figure-57xpfstiummbb32mct"><img id="57xpfstiummbb32mct" src="https://cdn.durable.co/blocks/10QIL10katCh3iOmS230nQcjlW4vYwCRhskzoGPAHNhOkWJW36H1unNPcPx8VO4N.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/10QIL10katCh3iOmS230nQcjlW4vYwCRhskzoGPAHNhOkWJW36H1unNPcPx8VO4N.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Create a Masking Policy: Implement a policy that uses the external function to detokenize data for authorized roles.<ul><li><figure id="figure-n53h98kc8ambb334mb"><img id="n53h98kc8ambb334mb" src="https://cdn.durable.co/blocks/13jIyCdIw7fHEK8leMy5ryltYVcpEKy9pFmDOmrpJehxUI1XegZ4Kfkg3YYs5FKm.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/13jIyCdIw7fHEK8leMy5ryltYVcpEKy9pFmDOmrpJehxUI1XegZ4Kfkg3YYs5FKm.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Apply the Policy to a Column: Use ALTER TABLE to set the masking policy on tokenized columns.<ul><li><figure id="figure-zftv2bk5nmbb34hbp"><img id="zftv2bk5nmbb34hbp" src="https://cdn.durable.co/blocks/19UTAa6u8l6Vk4tAt25LBuxeUYLelQotGtw4MD35yZhngIpFRfI2cRJLPQDTvZcw.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/19UTAa6u8l6Vk4tAt25LBuxeUYLelQotGtw4MD35yZhngIpFRfI2cRJLPQDTvZcw.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li><li>Test with Different Roles: Verify that only authorized roles can view detokenized data<ul><li><figure id="figure-gsvsrk3jumbb35wa8"><img id="gsvsrk3jumbb35wa8" src="https://cdn.durable.co/blocks/2fs9pYSRxKBRGo7dkY1RxmarL7RzaVPm82bFUHfd3u3XL3Cm9mrILfS8a9j6GHgQ.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/2fs9pYSRxKBRGo7dkY1RxmarL7RzaVPm82bFUHfd3u3XL3Cm9mrILfS8a9j6GHgQ.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure></li></ul></li></ol><h3>Use Cases for Tokenization</h3><ul><li>Payment processing (PCI DSS): Store only tokenized credit card numbers in Snowflake. Tokens are meaningless if breached. Actual card data is fetched only when needed (e.g. refund) via detokenization.</li><li>Identity data (HIPAA/PII): Personally Identifiable Information (SSNs, emails, phone numbers) are tokenized to minimize exposure. Analytics can still match on tokens if format-preserving, enabling joins without revealing data.</li><li>Multi-tenant/Dev environments: Dev/test accounts get tokenized data so no sensitive info is present, while prod systems store tokens with a secure link to real data.</li><li>Data sharing and collaboration: Shared tables contain tokens instead of real values, preventing any external party from seeing actual data. The token system owner controls detokenization.</li></ul><h3>Summary and Best Practices</h3>Both data masking and tokenization are essential strategies for protecting sensitive data in Snowflake. Choosing the appropriate method depends on the specific use case, data sensitivity, and compliance requirements.Best Practices:<ul><li>Least Privilege Access: Assign roles carefully to ensure users have only the necessary access to data.</li><li>Centralized Policy Management: Manage masking policies centrally to maintain consistency and ease of administration.</li><li>Regular Testing: Continuously test masking and tokenization implementations to ensure they function as intended.</li><li>Integration with Token Services: Ensure synchronization between Snowflake roles and external token services to prevent access issues.</li><li>Monitoring and Auditing: Utilize Snowflake's Access History and query logs to monitor data access and policy application.</li><li>Format Consistency: Use format-preserving tokenization if downstream systems require specific data formats.</li><li>Compliance Documentation: Maintain thorough documentation of data protection measures to satisfy audit and compliance requirements.</li></ul>Implementing these practices will enhance data security and ensure compliance within the Snowflake environment.

Data Masking vs Tokenization in Snowflake

<h2>Capturing CDC Data in Snowflake:</h2>In modern data architectures, data changes constantly. Orders are updated, user profiles change, inventory levels fluctuate.Capturing these changes efficiently is critical to building reliable analytics, reporting, and machine learning models.This is where Change Data Capture (CDC) comes in.Traditionally, CDC involved complex setups, third-party tools, or heavy extract-transform-load (ETL) pipelines.Snowflake simplifies CDC with built-in features that make it easier to track changes without rebuilding entire tables.<h3>What is Change Data Capture (CDC)?</h3>CDC is the process of recording changes — inserts, updates, and deletes — in a table over time.Instead of scanning an entire table to find differences:<ul><li>CDC lets us capture only the rows that changed.</li><li>This minimises compute, reduces costs, and speeds up data pipelines.</li></ul>In Snowflake, CDC is built around two main objects:<ul><li>Streams: Track changes to a table.</li><li>Tasks: Automate processing the captured changes.</li></ul>👉 CDC is like tracking edits in a shared Google Doc instead of re-reading the entire document each time.<h3>How Snowflake Captures CDC Data</h3>1. Streams: Tracking the ChangesA Stream in Snowflake records changes made to a table (inserts, updates, deletes) in real-time.When we query a stream:<ul><li>It shows us the changes since the last time it was queried.</li><li>It does not modify the source table.</li></ul>Think of Streams as "change tracking tables" automatically maintained by Snowflake.Key Points About Streams:<ul><li>Track inserts, updates, and deletes.</li><li>Support metadata columns like:<ul><li>METADATA$ACTION (INSERT/DELETE/UPDATE)</li><li>METADATA$ISUPDATE</li><li>METADATA$ROW_ID</li></ul></li><li>Streams reference the source table’s micro-partitions instead of storing data separately. &nbsp; 2. Tasks: Automating Change Processing</li></ul>A Task in Snowflake is a scheduled process that automates SQL execution.When used with Streams:<ul><li>A Task can regularly check if there are new changes.</li><li>It can move, transform, or load CDC data to another table automatically.</li></ul>Tasks allow us to:<ul><li>Set schedules (e.g., every 5 minutes).</li><li>Define dependencies (e.g., only run if the stream has new data).</li></ul><figure id="figure-xw1j4hdgfcma2rpsao"><img id="xw1j4hdgfcma2rpsao" src="https://cdn.durable.co/blocks/1aMERUQ8E0zA24ZUhPAgMzbEp4hRxe8ZtZLThADCZZmjOsakS7FbQtVjtmAG7PO5.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/1aMERUQ8E0zA24ZUhPAgMzbEp4hRxe8ZtZLThADCZZmjOsakS7FbQtVjtmAG7PO5.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><ul><li>Changes happen in the source table.</li><li>Stream captures these changes.</li><li>Task reads from the stream and updates the target table.</li></ul><h3>Capturing CDC Data in Snowflake</h3>Step 1: Create the Source Table<figure id="figure-h4gxr6urwtma2rtx0e"><img id="h4gxr6urwtma2rtx0e" src="https://cdn.durable.co/blocks/2cOamSkk8oiNbAPrvNMqnAh7teI1Qs7MnsIhTsLACsFbbtplEQMtkCOe0vmLzIYh.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/2cOamSkk8oiNbAPrvNMqnAh7teI1Qs7MnsIhTsLACsFbbtplEQMtkCOe0vmLzIYh.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Creates the main table where order data is stored.Step 2: Create a Stream on the Table<figure id="figure-s8ap5nyschma2rvw2y"><img id="s8ap5nyschma2rvw2y" src="https://cdn.durable.co/blocks/dPqYq3JZi7uvg6ZL4Xfbkh0Wsqxgc9ON1GuDeZBb73pWTmrA3KAIQr77NIrffAdY.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/dPqYq3JZi7uvg6ZL4Xfbkh0Wsqxgc9ON1GuDeZBb73pWTmrA3KAIQr77NIrffAdY.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Enables tracking of inserts, updates, and deletes on the orders table.Step 3: Query the Stream <figure id="figure-qqorpzmk7ma2rxrph"><img id="qqorpzmk7ma2rxrph" src="https://cdn.durable.co/blocks/28672WHj9l8KLBtdPqeodTekob10ohR5RDvP2dGcRA5rTRTcvrT51sgO68U5OHdD.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/28672WHj9l8KLBtdPqeodTekob10ohR5RDvP2dGcRA5rTRTcvrT51sgO68U5OHdD.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Retrieves the change records (CDC data) from the stream including metadata.&nbsp;Step 4: Process the Changes into a History Table<figure id="figure-rp69syp6sama2sm0fn"><img id="rp69syp6sama2sm0fn" src="https://cdn.durable.co/blocks/20y3qeX82NAgWInsyTHZ7n73t9UmqRiggdDuUv3mF3QR1RObSubGgQ5xUtbBnMpK.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/20y3qeX82NAgWInsyTHZ7n73t9UmqRiggdDuUv3mF3QR1RObSubGgQ5xUtbBnMpK.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Creates a table to store the change history of the orders table.<figure id="figure-9m3e7jx2xjma2snx3b"><img id="9m3e7jx2xjma2snx3b" src="https://cdn.durable.co/blocks/2bFKdg2ObXkn8sJjZi83CgmSDKnZCi799I09yiZsLanHgPuHnQ25RPIcs1VOBMdi.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/2bFKdg2ObXkn8sJjZi83CgmSDKnZCi799I09yiZsLanHgPuHnQ25RPIcs1VOBMdi.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Captures changes from the stream and logs them into the history table.Step 5: Automate with a Task<figure id="figure-sea7vqxmlmma2spu4v"><img id="sea7vqxmlmma2spu4v" src="https://cdn.durable.co/blocks/21kOavOCzo0eUt429U9XEVEn4qaBFKABauWjaOtvkEl6gBIChqDmdVAGxmBEzpm7.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/21kOavOCzo0eUt429U9XEVEn4qaBFKABauWjaOtvkEl6gBIChqDmdVAGxmBEzpm7.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>👉 Creates an automated task that loads changes into the history table every hour if there are updates.Real-World Scenario: E-commerce Platform OrdersImagine running an e-commerce platform where:<ul><li>Customers frequently place new orders.</li><li>Some orders are updated (e.g., address change, payment status).</li><li>Occasionally, orders are cancelled (deleted).</li></ul>Every time a customer places or modifies an order, you want your Snowflake database to automatically capture and process these changes.Using CDC:<ul><li>We capture these activities efficiently without reloading the full orders table.</li><li>Our analytics dashboard updates in near real-time.</li><li>Compliance teams get an auditable trail of order activities.</li></ul><h3>CDC Using External Tools</h3>Some popular tools help automate CDC without much manual coding:<ul><li>Fivetran</li><li>Hevo Data</li><li>HVR</li><li>Qlik Replicate</li></ul>These tools:<ul><li>Connect to your source (like MySQL, Postgres).</li><li>Detect changes automatically.</li><li>Push changes into Snowflake tables.</li></ul>Usually, you just set up connectors, schedule syncs, and you're done!&nbsp; Real-Life Example:Suppose your application database is PostgreSQL.Instead of building custom scripts, you use Fivetran:<ul><li>Fivetran captures new orders.</li><li>Fivetran pushes them into Snowflake every 5 minutes.</li><li>Your reports stay fresh with minimal work.</li></ul><h3>Manual CDC Approach (DIY)</h3>If your source doesn’t support built-in CDC, you can still do it manually:<ul><li>Add created_at and updated_at timestamps in your tables.</li><li>Query only records modified since the last sync.</li></ul>Step-by-StepStep 1: Add Timestamp Columns<figure id="figure-xdx5gufhclma2srzjd"><img id="xdx5gufhclma2srzjd" src="https://cdn.durable.co/blocks/bfYhUd9sWX20TJUdQa52alvM49IZW8eWhyPlBAFNmLsTUwYtrfE1Pxjirbyl7q15.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/bfYhUd9sWX20TJUdQa52alvM49IZW8eWhyPlBAFNmLsTUwYtrfE1Pxjirbyl7q15.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Step 2: Query for Changed Data<figure id="figure-j3vq75se0tma2sth2p"><img id="j3vq75se0tma2sth2p" src="https://cdn.durable.co/blocks/122G4UNsoCbwQoUh2Q6OBqe0ifMMXd3vyMBydPmIcEvJ4VVAJBUw1vJ7AOC72BDt.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/122G4UNsoCbwQoUh2Q6OBqe0ifMMXd3vyMBydPmIcEvJ4VVAJBUw1vJ7AOC72BDt.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Replace timestamp with the last sync time.Step 3: Insert or Update into SnowflakeUsing simple UPSERT/MERGE logic.Real-Life Example:<ul><li>You have a legacy MySQL database without CDC.</li><li>You add updated_at timestamps to all important tables.</li><li>Now you can pull only changed rows every night and load them into Snowflake.</li></ul><h3>Best Practices for Capturing CDC Data in Snowflake</h3><ol><li>Monitor Stream Offsets<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Streams maintain offsets.</li><li>Regularly consume the stream to avoid loss of changes.</li></ul></li><li>Handle Deletes Properly<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Deletions appear in streams.</li><li>Design how you treat them (e.g., soft-delete, permanent delete).</li></ul></li><li>Optimise Stream Usage<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Use append-only streams if you only track inserts.</li><li>Use full streams for inserts, updates, and deletes.</li></ul></li><li>Design for Reprocessing<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Ensure Tasks are idempotent.</li><li>Plan for safe retries without duplicates.</li></ul></li><li>Audit and Alert<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Monitor Task failures.</li><li>Set up alerts if a Task fails or a Stream is unconsumed.</li></ul></li></ol><h3>Common CDC Pitfalls to Avoid</h3><ol><li>Stream Retention Overruns<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Problem: Streams expire after retention period.</li><li>Tip: Query regularly or increase DATA_RETENTION_TIME_IN_DAYS.</li></ul></li><li>Ignoring Deletes in the Stream<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Problem: Deleted rows may appear active downstream.</li><li>Tip: Process DELETE actions properly.</li></ul></li><li>Task Failures Without Alerting<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Problem: Silent Task failures.</li><li>Tip: Set up monitoring and alerting.</li></ul></li><li>Overcomplicating the CDC Pipeline<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Problem: Complex transformations during CDC capture.</li><li>Tip: Keep CDC capture lightweight.</li></ul></li><li>Not Handling Reprocessing Carefully<ul data-mce-style="list-style-type: square;" style="list-style-type: square;"><li>Problem: Duplicate data when reprocessing.</li><li>Tip: Build idempotent pipelines. </li></ul></li></ol><figure id="figure-72wn8v1hsrma2t1f6s"><img id="72wn8v1hsrma2t1f6s" src="https://cdn.durable.co/blocks/1ekuAPwxbWnNw8fh38sXX8yzovxIYKqaHSNzc2xtZ5bUlChGaiKV0ukMudVoCJWe.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/1ekuAPwxbWnNw8fh38sXX8yzovxIYKqaHSNzc2xtZ5bUlChGaiKV0ukMudVoCJWe.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><h3>Why CDC in Snowflake Matters</h3><ul><li>Saves Money: Only processes changed data, not full tables.</li><li>Real-time Data: Your dashboards are always up-to-date.</li><li>Easy to Manage: Using Streams and Tasks, CDC pipelines are clean and automated.</li><li>Flexible Options: Whether you want built-in tools or external ones, Snowflake supports both.</li></ul><figure id="figure-2ozk610ycxma2t6ra3"><img id="2ozk610ycxma2t6ra3" src="https://cdn.durable.co/blocks/257C2vjnjhmZYx0f3EGVdTNVwVVY1ESVt2uSNawVL5A9DvL5KeWDvYMhsuQeiASt.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionX="undefined" data-positionY="undefined" data-fullWidth="false"/></figure><h3>Conclusion</h3>Capturing CDC data in Snowflake is simple yet powerful.Whether you use built-in Streams and Tasks, external tools, or manual methods, you can:<ul><li>Process less data</li><li>Get faster results</li><li>Save costs</li><li>Improve reliability</li></ul>Building efficient CDC pipelines lets us unlock real-time analytics and smarter business decisions, with minimal hassle

Capturing CDC Data in Snowflake

<h2>How Row Access Policies Work in Snowflake (And Why We Use Them)</h2>When we need to control who sees what rows in a Snowflake table, we use Row Access Policies.Unlike column-level masking, which hides sensitive fields, row access policies filter entire rows based on user attributes like roles or session variables.<h3>Row access policy</h3>A row access policy is a Snowflake object that acts as a dynamic filter applied whenever someone queries a table or view.<ul><li>It behaves like an automatic WHERE clause</li><li>It filters rows based on the current user or session</li><li>It applies during query time (not at data load time)</li><li>It works with SELECT, COPY INTO, and other operations </li></ul><figure id="figure-qz3r7s4tghma1a8pk6"><img id="qz3r7s4tghma1a8pk6" src="https://cdn.durable.co/blocks/22ymOk5BmyNxUPH7mBv8MJGpHTpfCaBBC0kI33sj6ps8RLERkp8acC9Lyq265C4I.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/22ymOk5BmyNxUPH7mBv8MJGpHTpfCaBBC0kI33sj6ps8RLERkp8acC9Lyq265C4I.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><h3>Creating a Row Access Policy</h3>We typically follow three steps:<ul><li>Create the policy using CREATE ROW ACCESS POLICY</li><li>Attach it to a table or view</li><li>Let Snowflake evaluate it every time the object is queried</li></ul>Example: Show Region-Specific Rows OnlyLet’s say we have a sales table with a region column. We want users to only see data for their assigned region.Step 1: Define the policy<figure id="figure-26jdoux1iama1adx66"><img id="26jdoux1iama1adx66" src="https://cdn.durable.co/blocks/29hynIJm1PexI0vOpVlfI3LYIQR8ASX1zl4VWpGqSNEa362X4qX0MPRigybRTpoD.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/29hynIJm1PexI0vOpVlfI3LYIQR8ASX1zl4VWpGqSNEa362X4qX0MPRigybRTpoD.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Step 2: Attach it to the table<figure id="figure-v710ylcmorma1ahfx7"><img id="v710ylcmorma1ahfx7" src="https://cdn.durable.co/blocks/15ZbVJUapoGQP9ShRGqbvR4ADePo86U2MiBiFYeiyM8xixI4faYFVzB8CfuXRJgG.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/15ZbVJUapoGQP9ShRGqbvR4ADePo86U2MiBiFYeiyM8xixI4faYFVzB8CfuXRJgG.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Now, if someone in the US region runs a query, they’ll only see rows where region = 'US'.<h3>How this is handled behind the scenes</h3>Snowflake rewrites the query under the hood using the policy logic. It doesn’t alter the table data itself.<figure id="figure-4gs2w0e69hma1ania3"><img id="4gs2w0e69hma1ania3" src="https://cdn.durable.co/blocks/8lDULzac9VW91aiSuCDpBQTNdFnO8EBBCyGUKe7bIJozbmcBJwyKyU8SizFdlfX5.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/8lDULzac9VW91aiSuCDpBQTNdFnO8EBBCyGUKe7bIJozbmcBJwyKyU8SizFdlfX5.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure><h3>Testing the Policy</h3>Before deploying a policy to production, test it like this:<ul><li>Set the session context (ALTER SESSION)</li><li>Run queries with different roles or users</li><li>Validate visibility of expected rows</li></ul><h3>Can You Apply Multiple Policies?</h3>Snowflake supports only one row access policy per table or view.To implement more complex rules, you’ll need to:<ul><li>Use logical operators inside a single policy</li><li>Check for multiple roles using IS_ROLE_IN_SESSION()</li><li>Apply CASE logic within the policy expression</li></ul>Combining Row Access and Column MaskingWe can use both together for layered security:<figure id="figure-suuzevzbkorma1aveuj"><img id="suuzevzbkorma1aveuj" src="https://cdn.durable.co/blocks/bgIy7fY9H7V35gESQ411DoroU6Qt2kMQykkXAOgcMahGaAmzsKw7gM5IeVbawil6.png" alt="" title="" class="object-cover bg-gray-100 rounded-lg md:rounded-xl lg:rounded-2xl" style="aspect-ratio: 16/9; object-position: center center;" data-corners="default" data-aspect="16:9" data-caption="" data-positionx="undefined" data-positiony="undefined" data-fullwidth="false" data-mce-src="https://cdn.durable.co/blocks/bgIy7fY9H7V35gESQ411DoroU6Qt2kMQykkXAOgcMahGaAmzsKw7gM5IeVbawil6.png" data-mce-style="aspect-ratio: 16/9; object-position: center center;"></figure>Row access controls which rows are shownColumn masking hides or transforms certain fields in those rows<h3>Managing and Auditing Policies</h3>Some helpful commands and tools:<ul><li>View all policies: SHOW ROW ACCESS POLICIES</li><li>See policy definitions: Query INFORMATION_SCHEMA.ROW_ACCESS_POLICIES</li><li>Remove a policy from a table: ALTER TABLE sales DROP ROW ACCESS POLICY;</li><li>Name your policies clearly, especially if you plan to version them (e.g., policy_sales_v1)</li></ul><h3>Useful Snowflake Functions</h3><table style="border-collapse: collapse; width: 100%;" border="1" data-mce-style="border-collapse: collapse; width: 100%;"><tbody><tr><td style="width: 50%;" data-mce-style="width: 50%;">Function</td><td style="width: 50%;" data-mce-style="width: 50%;">What it does</td></tr><tr><td style="width: 50%;" data-mce-style="width: 50%;">CURRENT_USER()</td><td style="width: 50%;" data-mce-style="width: 50%;">Returns the current user</td></tr><tr><td style="width: 50%;" data-mce-style="width: 50%;">CURRENT_ROLE()</td><td style="width: 50%;" data-mce-style="width: 50%;">Returns the current role</td></tr><tr><td style="width: 50%;" data-mce-style="width: 50%;">IS_ROLE_IN_SESSION() </td><td style="width: 50%;" data-mce-style="width: 50%;">Checks if a role is active</td></tr><tr><td style="width: 50%;" data-mce-style="width: 50%;">CURRENT_REGION()</td><td style="width: 50%;" data-mce-style="width: 50%;">Custom or session-based region</td></tr><tr><td style="width: 50%;" data-mce-style="width: 50%;">SESSION_USER()</td><td style="width: 50%;" data-mce-style="width: 50%;">Returns the session’s authenticated user</td></tr></tbody></table>These functions help make policies more flexible and context-aware.<h3>How Row Access Differs from Column Masking</h3><table style="border-collapse: collapse; width: 100%;" border="1"><tbody><tr><td style="width: 33.3325%;">Feature</td><td style="width: 33.3325%;">Row Access Policy</td><td style="width: 33.335%;">Column Masking</td></tr><tr><td style="width: 33.3325%;">Filters</td><td style="width: 33.3325%;">Whole rows</td><td style="width: 33.335%;">Specific columns</td></tr><tr><td style="width: 33.3325%;">Use case</td><td style="width: 33.3325%;">Limit access by geography, department, etc.</td><td style="width: 33.335%;">Hide sensitive fields like SSNs</td></tr><tr><td style="width: 33.3325%;">Based on</td><td style="width: 33.3325%;">User, role, session context</td><td style="width: 33.335%;">User, role, session context</td></tr><tr><td style="width: 33.3325%;">Can combine</td><td style="width: 33.3325%;">Yes</td><td style="width: 33.335%;">Yes</td></tr></tbody></table>Use row access when what a user can see depends on where they belong (e.g., region or department).Use column masking when what fields a user can see depends on their level of clearance.Row Access Policy vs Column masking<ul><li>Use Row Access policy to limit /filter data based on certain condition. use column masking to hide sensitive fields.</li><li>For Example - use Row Access policy to limit access by geography, department, etc. meanwhile use column masking to hide sensitive fields like SSNs, IDs</li></ul><h3>Conclusion</h3>Row Access Policies help us control visibility at the row level. They’re easy to set up and flexible enough for complex scenarios.We’ve used them to build region-specific dashboards, protect internal data by team, and support secure self-service reporting — all without duplicating data.When used together with column masking and access control, they give us a clean way to manage security at scale.

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