FAQ

  1. Why no GUI – what is the benefit?
    • Coding is more efficient, but a graphical representation of the job is generated for inspection and overview purposes.
    • Several (hundreds of) similar ETL jobs can be generated at once.
    • Data definitions (DDLs) can be updated automatically.
    • More versatile and flexible; unusual or custom things can be easily included.
  2. What programming languages are needed to use EVL Tool?
    • Basics of C++ and bash are usually enough. Here, “basics of” means knowing what the pointer is in C++, and what ${…} and $(…) are in bash.
  3. How easy is it for a user to extend functionalities?
    • There are several core ETL components and some others based on these. You can build your own component based on existing ones, or build a completely new one. 
  4. Will self-developed extensions be compatible with future versions of EVL Tool?
    • Recommendations are provided in the documentation, following these will ensure compatibility with future versions of EVL Tool.
  5. What does transparency, in terms of EVL Tool, mean?
    • Readable, open source code. Auditing and troubleshooting code is easy.
  6. Is EVL Tool a single tool or does it consist of different modules?
    • There is an ETL tool – EVL – then EVL Workflow, which orchestrates EVL (and other) jobs; the third component is EVL Manager, which is used to monitor and manage EVL and EVL Workflow. EVL, and EVL Workflow can be used independently.
  7. What administration is required for EVL Tool?
    • Only install and update. This can be done by manually replacing a single folder, or with a Linux package manager (rpm for RedHat distributions, or deb on Debian distros).
  8. How is security managed?
    • At the system level. Any OS utilities, such as Kerberos, can be employed.  Some ETL products on the market claim to support Kerberos in the application, but the reality of this often means administering Kerberos at the OS level AND in the application. By relying on system security EVL skips this redundant configuration and is a much more flexible, and easy to use, tool.
  9. How does EVL Tool manage user permissions?
    • This is up to the system. LDAP or simply standard Linux user permissions can be used.
  10. Does EVL Tool provide backup functionalities?
    • No, This shouldn’t be part of ETL itself, backups should managed by dedicated ETL jobs written in EVL.
  11. What connectors are available?
    • UnixODBC is integrated into EVL. With drivers, EVL can connect to any DBMS.
    • Native Teradata and PosgreSQL connections are implemented at the moment, with much better performance compared to ODBC.
    • Kafka streams can also be consumed and produced.
  12. Is a SAP connector available?
    • Currently over ODBC.
  13. How does an EVL template look like?
    • A text file, that is run as shell script, with components. For Example:
      Read    input.csv INPUT    input.evd --text-input
      Map     INPUT     MAPPED   input.evd output.evd mapping.evm
      WriteTD MAPPED    SOME_DB.SOME_TABLE output.evd --append
  14. Does EVL Tool support real-time streaming?
    • Yes, Kafka for example.