Explain the difference between ETL and ELT.

Question

Accepted Answer

ETL extracts, transforms, and loads data, while ELT loads data first and transforms it later, often in a data lake.

ETL (Extract, Transform, Load) processes data before loading it into the target system.
ELT (Extract, Load, Transform) loads raw data into the target system and transforms it afterward.
ETL is typically used in traditional data warehousing environments.
ELT is more common in cloud-based data lakes, allowing for greater flexibility.
Example of ETL: Data from multiple sources is cleaned and aggregated before loading into a data warehouse.
Example of ELT: Raw data from IoT devices is loaded into a data lake and transformed as needed for analysis.

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