select
    col as original,
    col::double as val_double,
    col::float as val_float,
    col::decimal(10,4) as val_decimal,
    to_number(col, '99999.99999') as val_tonum
from int_fx_conversion_rate;

The original value of col is a string such as '1.2345' out to 4 decimal places. When I run this above, all of the casted versions come out rounded to 2 decimal places (1.23). How do I get all the decimals?