I load data into Fact table from our ERP system and I have a field called Payer. I then Left Join to Fact data in a spreadsheet that has the fields Payer and Exclude. The Exclude field will have the value of 'Y' in it. Now the Exclude field in Fact will have a 'Y' or it will be Null.
After I have done the above (Fact table is now loaded with Payer and Exclude fields, I want to go through a differnet logic process, something like if Payer = X and some other field = Z Change the Exclude field from Y to N. Is there a way to overwrite the value of a field?