It seems like synapser isn't properly handling R Date objects when storing Synapse Tables.
You can reproduce using the example code below:
I ran into this error when trying to write a reproducible example for different error I was seeing:
Even though all the columns in the dataframe that were being stored to DATE Synapse columns were either of class "Date" or ("POSIXct" "POSIXt").
I'm using synapser 0.6.56