Last Update: 6/11/2021
ASCII file import may be slow if the file has many columns and a sparkline is being created for each. You can turn sparklines on or off when importing.
The Data Columns page of the Import Wizard dialog and the Import Options for Single and Multiple ASCII Import have a control which can be set to Yes, No or Yes (if less than 50 columns).
If you are using a Data Connector to import CSV or MS Excel data, you can disable sparklines on import by setting @IMPS = 0. See FAQ-708 How do I permanently change the value of a system variable? for information on changing the value of a system variable.