Summary:
I need to create a subselect with MAX(initialDate) GROUP BY id but it was not possible.

Error:
All date fields from my table were excluded from the list of columns in the Summarize tool.

How to Reproduce:

1. Create a DataSource pointing to your table. Your table must have at least one DATE column.
2. Create a Summarize tool from your datasource.
3. In Calculate the, choose Maximum.
4. In of column, look for your date field.