Again, as I said, I got MySQL errors when inserting '1' values through install.sql, but I fixed that by turning them into integers.
So, a proper INSERT would also be
INSERT INTO table SET bit_field = 1;
I could simply test for is_integer() before inserting some imported data, and doing without single quotes in this case...
Or is it that can_collapse accepts more values than 0 or 1? Anything I converted to BIT(1) was thoroughly tested (AFAIK) against this possibility (a lazy habit of earlier SMF developers, I think!)