Time Generator Node and Flow Variable Input

Dear all,

I cannot convince the Time Generator node to respect external variable input. I want to provide a start and end date through the flow variables. This only works with number-of-generated-rows variable.

I suspect this problem is due to posix time being long and not int. I tried to overcome this with double and string without success. Also setting output variables causes an out of range error.

This is sad, as I cannot use this node in an automated fashion which practically makes it useless in my case. Any suggestions?

With best regards,


I experienced these problems too, without support of datetime variables it is difficult to do many tasks in financial analysis. Hope next versions will fix it.

I solved problem with Time Generator using PostgreSQL and DatabaseReader. If you use PostgreSQL (maybee other database systems like MS SQL Server), you can make queries like:

SELECT time::timestamp(0) FROM
generate_series('$${Sfrom}$$', '$${Sto}$$', interval '1 minute') time(i)

which returns exactly what you wants. 'from' and 'to' are string (formatted date) variables. Hope it helps.


there seem to be various workarounds - another flavour is to use an R snippet as attached.

With best regards,

This problem still persists in the current version of Knime 2.11.2

As a feature request it would be nice to select an interval to which the time series is generated e.g. 15min as in R (in addition to input number of rows).

Agreeing that being able to pass Flow Variables to the Time Generator node would be extremely helpful. For my purposes, the node is unusable without such a feature.



in cases like this, you can generate your own node :)

We don't have date/time variables, hence you need to convert them to a string. Take a look into the attached workflow to see how this works.

The workflow generates all dates between the current time and a fixed start date.

Best, Iris

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