ELT vs ETL
ELT (Extract, Load, Transform) and ETL (Extract, Transform, Load) both come up in technology conversations and get confused. Here's the plain-English difference, side by side, so you can use each one with confidence.
The key difference: ELT refers to extract, load, transform, while ETL refers to extract, transform, load — they describe different things even when they show up in the same sentence.
ELT — Extract, Load, Transform
Modern variant where raw data is loaded into the warehouse first and transformed in-place using SQL. ELT is the cloud-warehouse default — cheaper storage, more flexible modeling.
ETL — Extract, Transform, Load
The classic pattern for moving data: pull from sources, reshape it, then load into a warehouse. ETL was the dominant approach when storage was expensive and compute was scarce.
When to use ELT
Reach for "ELT" when the conversation is specifically about extract, load, transform. Modern variant where raw data is loaded into the warehouse first and transformed in-place using SQL. ELT is the cloud-warehouse default — cheaper storage, more flexible modeling.
When to use ETL
Reach for "ETL" when the conversation is specifically about extract, transform, load. The classic pattern for moving data: pull from sources, reshape it, then load into a warehouse. ETL was the dominant approach when storage was expensive and compute was scarce.
FAQs
What is the difference between ELT and ETL?
ELT stands for Extract, Load, Transform — Modern variant where raw data is loaded into the warehouse first and transformed in-place using SQL. ELT is the cloud-warehouse default — cheaper storage, more flexible modeling. ETL stands for Extract, Transform, Load — The classic pattern for moving data: pull from sources, reshape it, then load into a warehouse. ETL was the dominant approach when storage was expensive and compute was scarce.
Are ELT and ETL the same thing?
No. They're often used in the same conversation because they're related, but they describe different concepts. ELT = Extract, Load, Transform. ETL = Extract, Transform, Load.
When should I use ELT vs ETL?
Use ELT when you're specifically referring to extract, load, transform. Use ETL when the topic is extract, transform, load.