What is ELT - 7.3

Talend Open Studio User Guide

Talend Open Studio for Big Data
Talend Open Studio for Data Integration
Talend Open Studio for Data Quality
Talend Open Studio for ESB
Talend Studio
Design and Development
Last publication date
Available in...

Open Studio for Big Data

Open Studio for Data Integration

Open Studio for ESB

Extract, Load and Transform (ELT) is a data manipulation process in database usage, especially in data warehousing. Different from the traditional ETL (Extract, Transform, Load) mode, in ELT, data is extracted, loaded into the database and then is transformed where it sits in the database, prior to use. This data is migrated in bulk according to the data set and the transformation process occurs after the data has been loaded into the targeted DBMS in its raw format. This way, less stress is placed on the network and larger throughput is gained.

However, the ELT mode is certainly not optimal for all situations, for example,

  • As SQL is less powerful than Java, the scope of available data transformations is limited.

  • ELT requires users that have high proficiency in SQL tuning and DBMS tuning.

  • Using ELT with Talend Studio, you cannot pass or reject one single row of data as you can do in ETL. For more information about row rejection, see Row connection.

Based on the advantages and disadvantages of ELT, the SQL templates are designed as the ELT facilitation requires.