Update: I have recently published a free Talend for Data Integration eBook
ETL (Extraction Tranformation Loading) is the process in which data is extracted from different sources (database, file, web services, etc), is then processed (value replacements, computations, etc) and finally loaded on another destination (database, file, web, etc). ETL is a key process in Business Intelligence and Datawarehouse management.
Furthemore, ETL tools are very usefull to perform data management tasks when large amount of data is involved.
Pentaho Kettle and Talend Open Studio
Pentaho Data Integration PDI (Kettle) is the default ETL tool for the Pentaho ecosystem. On its very intuitive graphical editor (Spoon) it is easy to build Data Integration procedures. The procedures can be run by Kettle runtime in different ways: Using the command line utility (Pan), a small server (Carte), a database repository (Kitchen) or directly from the IDE (Spoon). Procedures are saved in XML files and interpreted by a Java library which is required to run the ETL tasks.
Talend Open Studio is the ETL tool developed by Talend, a fast growing company focused on data integration and data management solutions. Talend uses an user friendly and comprehensive IDE (similar to Pentaho Kettle's) to design the procedures. Procedures can be tested on the IDE and compiled in Java code. The Java generated code can be modified to achieve greater control and flexibility.
Both tools are reliable, performant, user friendly and cross plaform (Java based). The main difference is that Kettle is an interpreter of ELT procedures saved in XML format, while Talend Open Studio is a Java code generator tool.
Learning curve, easy to use, documentation
Both Pentaho Kettle and Talend Open Studio are user friendly tools. A typical user with a good background in data management (SQL, databases, file formatting, programming basics, etc) becoming productive is a matter of days / weeks.
Kettle and Talend comes with a graphical tool which is very intuitive and helps the entire ETL process from the design to test and deployment.
Pentaho Data Integration (Kettle)
Talend Open Studio
Pentaho Kettle IDE is slightly easier to start with but also less comprehensive when compated to Talend. The learning curve for Talend Open Studio is more steep, however its flexibility and power greatly compensate the first impact.
One of Talend Open Studio requirements is to define the correct schema of the data to be processed and the IDE helps a lot on this task. Kettle is more flexible on this and the ETL procedures can be built quickly. Anyway metadata definition in Talend is an important feature and helps the maintenability and reliability of the procedure when deployed in production.
Talend Open Studio and Pentaho Kettle are both user friendly, well documented and have a strong comunity support. Talend Open Studio requires more initial effort to get started however its great potential is highly appreciated from the beginning.
Reliability, maturity, support
In the enterprise Open Source comunity and real world implementations make a huge difference. Both Talend and Pentaho have strong community support are healthy, well known companies. Open Source Business Intelligence is growing fast and real world applications are widespread.
In this scenario Talend and Pentaho offers some of the most deployed Open Source ETL tools, used in several mission critical implementations.
Talend is more focused on data integration, data quality and data management solutions, while Pentaho is focused on Business Intelligence. Talend Open Studio is very actively developed by Talend in a rich data integration ecosystem, while Kettle is an important project for Pentaho, even if less developed and extended than Talend.
Pentaho and Talend solutions are very reliable, mature and fast growing. Real world enterprise implementations are becoming common in both cases. Support services are available via subscriptions and books or direct consulting services are also easy to find.
Components, technology and features
Talend Open Studio is an Eclipse based Java tool. The procedures are then compiled in Java bytecode during the deployment, this means that the entire Java ecosystem can be potentially used.
Components and features are numerous, mixing both general proupose tools and very specific components. Talend provides vendor specific sets of RDBMS, NoSQL, Big Data components among generic ones, this approach enables the support to both vendor specific features and generic database features.
Talend is more features rich and has a more technology compared to Kettle. In Talend the full Java ecosystem can be used and it's ease to use vendor specific database features. Kettle is also a good tool, with everything necessary to build even complex ETL procedures.
Some interesting benchmarks for Kettle and Open Studio can be found at:
With the Open Source version of Kettle it is easy to implement a clustered ETL environment. These (and further) advanced features are avaiable in the commercial version of Talend Open Studio.
Talend procedures, when compiled in Java bytecode, are compact, fast and easy to be deployed. Pentaho Kettle procedures are interpreted and can be sometimes slower than Talend. This depends on the type of the component and the complexity of the procedures.
Deployment and integration in BI platforms
Talend Open Studio (TOS) is a generic ETL and Data Management tool also integrated in the SpagoBI and Jasper Server BI platforms. Procedures are compiled in small Java packages, easily deployable and runnable in any Java enabled environment.
Kettle (PDI) is the default tool in Pentaho Business Intelligence Suite. The procedures can be also executed outside the Pentaho platform, provided that all the Kettle libraries and Java interpreter are installed.
Kettle makes it is easy to deploy procedures in clustered enviroments and save them in a database table. In Talend these and further features are avaliable in the subscription version. Like Talend, Kettle also provides a subscription support.
Talend is very easy to deploy as a standalone Java application, and is the default ETL tool for SpagoBI and JasperServer. Kettle is the default tool for Pentaho Business Intelligence and requires the Kettle core libraries when deployed outside the Pentaho platform.
Both products are well known, reliable and user frienldy Open Source tools. Commercial versions with additional support and features are also avaiable.
Kettle is the default ETL tool for Pentaho Business Intelligence Suite, it's easy to learn and very common in Pentaho solutions. Kettle provides a simple enviroment focused on ETL procedures.
Talend is a more generally prouposed and comprehensive tool, used by default in JasperServer an SpagoBI. Procedures can also be used in Pentaho or in standalone applications with ease.
The main difference is that Kettle is an interpreter mainly used for the ELT tasks, while Talend is a code generator part of a complete Data Management ecosystem.
Pentaho Kettle is very easy to use and a good solution in Pentaho enviroments. Talend is a more general propouse Data Management platform that can be used in conjuction with its Talend ESB, Talend Data Quality and Talend MDM companions.
Talend Open Studio can be downloaded at http://www.talend.com/download, and Pentaho Data Integration (Kettle) at http://sourceforge.net/projects/pentaho/files/. Commerical versions are avaiable at Talend and Penthao web sites.