Koen Verbeeck builds a tally table:
Sometimes you need a numbers table (also called tally table) when you’re working with data. It’s a table with one single integer column that contains incremental numbers (0,1,2,3,4,…). In a database, it’s fairly easy to generate using either cross-joins or a generator function (GENERATE_SERIES in T-SQL). Recently, I needed such a table in Power BI Desktop. Suppose you don’t have a database as a source (or maybe you cannot change the database), so we need to generate this in Power Query.
Read on to see how.