ETL vs ELT: What Is the Difference?
By Karthick Selvam · Published
Two patterns for moving and transforming data, differing in where the transformation happens.
ETL
Extract, Transform, Load: data is transformed before landing in the target. Common where warehouse compute was expensive or data must be masked first.
ELT
Extract, Load, Transform: raw data lands first and is transformed inside a scalable warehouse or lakehouse, often with SQL-based tools.
Which to choose
Most modern cloud teams default to ELT for flexibility and auditability, keeping ETL for sensitive data that must be cleaned or masked before landing.
Frequently asked questions
Is ELT always better?
No. It depends on data sensitivity, platform and cost.
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