Hi,  Thanks for your response - I tried doing the above and I assume my apply changes should  look like: 

dlt.apply_changes(
    target = "table_old", #<-- this is the actual delta table 
    source = "source_table_dlt",
    keys=["id"],
    sequence_by= col("import_date"))
 
When I run the pipeline, I get the following error: 

com.databricks.pipelines.common.errors.DLTAnalysisException: Could not materialize 'table_old' because a MANAGED table already exists with that name.
 
Am I getting this because table_old is a delta table and not a delta live table ? Appreciate any help in resolving this. TIA.