DAX New Column - if values in one column are blank use the values from another column on a different

[PhoenixBird66]

I'm trying to create a new column (Description3) using DAX which says if the value in the "Description1" column is blank or null, then use the value of another column [Description2] from a different table.

If both are blank, then leave it blank.

Any ideas how best to do this?

Thanks

[PattemManohar]

@PhoenixBird66 If you want to retrieve a value from a column in another table, then try using "LOOKUPVALUE" function in your new calculated column.