I added a clustered index to the tables and it seems to have fixed the issue.

Thanks for your help.

Thanks for your help, that's what I did. I'm going to make the recommended changes and see what happens.

I figured out how to get the plan in text format.

|--Table Insert(OBJECT[DTM].[dbo].[t_DTM_DATA_STAGING2]), SET[DTM].[dbo].[t_DTM_DATA_STAGING2].[CP] = [DTM].[dbo].[t_DTM_DATA_STAGING].[CP],[DTM].[dbo].[t_DTM_DATA_STAGING2].[CO] =...

I ran the Display Est. Execution plan, not sure how I can post it as it's a graphical image.

It is doing a Table scan on t_DTM_DATA_STAGING. I don't...

Thanks for your help.