You want to add a simple calculated column to identify a current record using some criteria. An example might be the Slow Changing Dimension task in SSIS, which only provides a null end date for new records inserted into the table.
The following example adds a calculated column called “IsCurrent” to the table “YourDimensionTable” based on records that have a null end date for the column “date_to”.
ALTER TABLE YourDimensionTable ADD IsCurrent AS CASE WHEN date_to is null then 'Yes' else 'No' end GO
Now you have provided a more intuitive method for identifying or slicing current records i.e.
SELECT * FROM YourDimensionTable WHERE IsCurrent = 'Yes'
On a side, there is a reference here for customising the scd task to cater for custom dates…