You can reach the corresponding dialog in PARTlinkManager via Extras --> Database --> Change/create database columns [Modify/create database columns] -> Remove tab page.
All columns created in the database are displayed in the list field under Column name.
Select the column to be removed.
Confirm with OK.
Note
If the database does not support the deletion of columns (e.g. SQLite), the Remove tab page is hidden.
The database is not accessed! Deletion only applies to PARTsolutions data.