Empty column can be transfer into Date in Table Validator

I want to use the table validator to check the columns and date type for my input tables. But I found that if the input table is empty, columns can not be transform into Date. But if I use the “transformation” tab in Excel Reader to configure the column type, it works.



add on some information:
failed when choose “Use new schema” in Excel Writer
image


Hello @cuimaple,

According to the error message, the conversion only works for Boolean, Double, Int, Long, and String types, and is not available for Local Date.

The source code is open-source, so check it out if you’re curious.
https://raw.githubusercontent.com/knime/knime-base/d74a4f7a6f094c0deee350651978620c0abe0e6c/org.knime.base/src/org/knime/base/node/preproc/datavalidator/DataValidatorColConfiguration.java

We can only hope that Local Date support will be implemented someday!

Thanks,

The point is that for the same blank input table, I can use “transformation” in excel reader to change the blank column to Local Date. But when I use table validator to change the blank column to Local Date, it failed.