I understand that you have created a derived view in the Virtual DataPort Administration Tool and tried to rename the columns of the derived view using **ALTER VIEW **syntax.
If that is the case, I could modify the column names of a derived view using VQL by executing the **CREATE OR REPLACE VIEW** statement like:
`CREATE OR REPLACE VIEW VIEW_NAME AS SELECT FIELD_NAME AS ALIAS_NAME,.... from view_name`
Alternatively, I could use the "**Edit > Output**" tab of the derived view in Virtual DataPort Administration Tool in order to rename the fields using GUI.
You can refer to the [Modifying a Derived View](https://community.denodo.com/docs/html/browse/latest/en/vdp/vql/defining_a_derived_view/modifying_a_derived_view/modifying_a_derived_view) section under the Virtual DataPort VQL Guide for more information.
Hope this helps!