[ODI 11g] ETL Vs ELT Approach

ETL vs ELT Approach

ETL:

Traditional ETL tools operate by the following

1. First Extracting the data from various sources

2. Transform the data on a proprietary, middle-tier ETL engine, and then

3. Loading the transformed data the target data warehouse or integration server.

ELT:


It incoporates the best aspects of manual coding and automated code-generation approaches.

It changes the following

1. where and how data transformation takes place,

2. and leverages existing developer skills, RDBMS engines and server hardware to the greatest extent possible.

3. It moves the data transformation step to the target RDBMS

ELT tools operate by the following:

1. Extract the data from the source tables

2. Load the tables into the destination server, and then

3. Transform the data on the target RDBMS using native SQL operators.

E-LT there is no need for a middle-tier engine or server