Andl Adds Relational Algebra to Knime

Knime is a visual programming language for analysing and displaying data. It models the flow of data in tables as a graphical workflow, made up of nodes and edges. To learn more about Knime, go here: https://www.knime.com/.

AndlRaKnime provides a set of nodes that implement the Relational Algebra. Using these nodes allows you to perform SQL-like queries on a wide variety of non-SQL data sources, such as CSV files or data retrieved online. For more about the Relational Algebra see here: https://en.wikipedia.org/wiki/Relational_algebra.

The set of nodes is currently:

  • Selection (as a Boolean expression)
  • Projection
  • Join (and Semijoin, Antijoin)
  • Rename
  • Union (and Minus, Intersection, Difference)
  • New Value (as a JEXL expression).

For more about JEXL see here: http://commons.apache.org/proper/commons-jexl/.

Sample workflows are included to demonstrate each of these these capabilities. Here is an example.

Knime workflow

An early version of AndlRaKnime has been released for comment and feedback.

You can find it here: https://github.com/david-pfx/AndlRaKnime

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