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Halt on condition

This action aborts project execution if specified condition is not fulfilled. Error message can be customized to provide more insight into the cause of interruption.

The purpose of this action is to monitor data quality and prevent projects from producing incorrect results or exporting incorrect data.


Let's assume we expect amounts to be numbers in all rows.

Before transformation:

Province Amount Total Tax
ON 1000 125
BC #N/A 187.5
QC 2000 270

Defining a condition as follows

 not isnumber([Amount])

will make the action stop project execution, because one of the values in column Amount is not a number.


The condition must return either TRUE or FALSE for each row. If, for some reason, it returns an error then the action will also fail.

If the condition is global (i.e. doesn't refer any field) then it's still evaluated even if the dataset is empty.

See also:

transformations/halt.txt · Last modified: 2021/04/02 13:48 by dmitry