In Dashboard Designer we are using the SQL Table Widget but unable to determine how we can add columns.
The table only shows two columns, but I do not see any Add Column button like we have on List Widget.
How can I add columns?
For SQL table widgets in the Dashboard Designer, you do not need to specify a number of columns.
Once you create a query and link it to the widget, the number of columns will be automatically set to the appropriate number based on how many columns the query returns.
So if the query in your SQL Datasource returns, e.g. 5 columns, the widget will automatically expand to 5 columns to accommodate the results.
See the following documentation for more details on assigning data sources to widgets including SQL Data Sources: