Extract, load, transform
This article relies largely or entirely on a single source. (November 2023) |
Extract, load, transform (ELT) is an alternative to extract, transform, load (ETL) used with data lake implementations. In contrast to ETL, in ELT models the data is not transformed on entry to the data lake, but stored in its original raw format. This enables faster loading times. However, ELT requires sufficient processing power within the data processing engine to carry out the transformation on demand, to return the results in a timely manner.[1][2] Since the data is not processed on entry to the data lake, the query and schema do not need to be defined a priori (although often the schema will be available during load since many data sources are extracts from databases or similar structured data systems and hence have an associated schema). ELT is a data pipeline model.[3][4]
Benefits
[edit | edit source]Some of the benefits of an ELT process include speed and the ability to handle both structured and unstructured data.[5]
Cloud data lake components
[edit | edit source]Common storage options
[edit | edit source]- AWS
- Azure
- Azure Blob Storage
- GCP
- Google Storage (GCS)
Querying
[edit | edit source]- AWS
- Redshift Spectrum
- Athena
- EMR (Presto)
- Azure
- GCP
- BigQuery
References
[edit | edit source]- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Using Redshift Spectrum to load data pipelines Published by deductive.com on January 17, 2018, retrieved on April 3, 2019.
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
External links
[edit | edit source]- Dull, Tamara, "The Data Lake Debate: Pro is Up First", smartdatacollective.com, March 20, 2015.
- ELT: Extract, Load, and Transform A Complete Guide | Astera Software
