Here is some sample data from 2 tables I have
I am trying to write an update query that will :
update the Customer flag to 'T' on Customer Order table If the Customer Number exists in the Mail Customer table.
update the Customer flag to 'F' on Customer Order table If the Customer Number does not exist in the Mail Customer table.
Given data above table below should look like below after query
Was thinking of using case with inner join but not sure how