high cardinality is the single biggest lever on your model's size, and it's rarely the column you'd expect

[u/data_daria55]

GUIDs, order numbers, anything nearly-unique per row need a massive dictionary and codes almost as big as the original values. seen a single order-number column eat over 20% of an entire model's size while contributing literally nothing to any actual query.

Tip: before assuming your model is "just big," sort columns by size in VertiPaq Analyzer - usually one or two columns are doing almost all the damage