Demo Options for matching based on non-equal values

Workflow demonstrating some ways to perform a join where part of the join condition is not based on perfect equality. The Joiner node can only join using "equal", so the joiner can be used to perform the part of the join it can produce, and then other standard nodes can be used together to filter those rows that match the remainder of the condition, in a similar way to a Rule Based Row Filter would work. In some cases a Rule Based Row Filter could be used here, but where calculations are required, the Rule nodes are not capable of the required matching, so String Manipulation or Math Formula nodes can be utlised instead.

Another option is to use Math Formula to provide the lower and upper range boundaries for one of the values and then use a Rule-Based Row Filter to keep only those rows where the other Value is within that range

Alternatively, a custom component can be used to provide a "custom condition" utilising a SQL condition compatible with the H2 database

https://hub.knime.com/takbb/spaces/Public/latest/Components/Joiner%20Components/Join%20Custom%20Condition%20-%20indexed

And a further possibility, for greater flexibility and allowing the query to be written using DB Query nodes, components can be used for creating copies of the data in an H2 database:

https://hub.knime.com/takbb/spaces/Public/latest/Components/Joiner%20Components/KNIME%20Table%20Session%20Connector

and

https://hub.knime.com/takbb/spaces/Public/latest/Components/Joiner%20Components/KNIME%20Table%20Connector

External resources

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