Understanding Data Unloading in Snowflake

Learning Objectives

Understand the data unloading process in Snowflake

Differentiate how data unloading differs for an internal and an external stage

Learn how to use COPY INTO options effectively to control file generation and optimize data exports.

Overview

Vinay, a Data Engineer at GlobalMart, needed to export data from Snowflake to ADLS but found no direct export option. Seeking help, Rahul, the Senior Architect, introduced stages, COPY INTO, and GET for efficient data unloading.

Vinay learned about file splitting, and key COPY options like OVERWRITE, SINGLE, and MAX_FILE_SIZE. With this knowledge, he was ready to optimize data exports while ensuring performance and control.

Prerequisites

Knowledge of Snowflake Data Architecture
Familiarity with at least one data platform (AWS, Azure, GCP, etc.)
Understanding of stages, file formats and COPY command in Snowflake