Friday, March 28, 2008
ETL Vs ELT
For past decade ETL ( Extract Transform Load) has been very commonly used architecture for most of the ETL tools like Informatica, DataStage, Abnitio etc.... But now the database servers are getting very powerful and it is making less sense to go by ETL architecture.
What is ETL : ETL is approach where most of the heavy lifting transformation is performed outside the database server on ETL server. In this approach data is first extracted from the source and cached in ETL server. Then data is transformed and mapped back to Database native datatype and loaded. There is dependency on Database sever and ETL server Latency.
ELT approach - Data is once loaded into the database and all transformation is performed on the database server. This approach removes any dependency on ETL server and Database server Latency. And it also remove one extra hope of I/O from DB server to ETL server.
Different ETL tools are providing architecture to perform efficient ELT and still maintain all code metadata in ETL tool repository. ETL tool will also capture all run time statistics. Informatica pushdown license enable the ELT architecture.
For past decade ETL ( Extract Transform Load) has been very commonly used architecture for most of the ETL tools like Informatica, DataStage, Abnitio etc.... But now the database servers are getting very powerful and it is making less sense to go by ETL architecture.
What is ETL : ETL is approach where most of the heavy lifting transformation is performed outside the database server on ETL server. In this approach data is first extracted from the source and cached in ETL server. Then data is transformed and mapped back to Database native datatype and loaded. There is dependency on Database sever and ETL server Latency.
ELT approach - Data is once loaded into the database and all transformation is performed on the database server. This approach removes any dependency on ETL server and Database server Latency. And it also remove one extra hope of I/O from DB server to ETL server.
Different ETL tools are providing architecture to perform efficient ELT and still maintain all code metadata in ETL tool repository. ETL tool will also capture all run time statistics. Informatica pushdown license enable the ELT architecture.
Labels: ETL VS ELT
# posted by Arvind @ 7:23 AM 
