This is more of a best practices issue than an intractable problem, but I thought I'd see how other people might approach this:
I pull in new sales data weekly to append to a dataset I prepare for reporting. Due to the idiosyncrasies of sales patterns and our data warehouse some weeks this will mean I pull six days of data, others I pull seven. Normally I just manually adjust the filter tool in the attached screenshot between '<' and '<=' depending on the dates present in each edition of the sales data, but I'm sure there's a better way to configure this.
Would using a combination of temporary columns and filtering out duplicates after the join be an efficient way to approach this? Using a Unique tool seems like it may be prone to error, but maybe I'm overthinking it and should just take the time to fine-tune a workflow segment using Unique.