Local authorization queries must be SELECT statements with the result column count matching the wildcard count, and fact signatures cant overlap. Count columns before running.

Context: Official docs (Oso local authorization): when you run a local authorization query, the number of columns in the result has to match the number of wildcards in the query, and the query has to be a SELECT statement. Overlapping fact signatures are rejected too. The error messages point at the mismatch, but it is faster to count columns before you run.