Question: storing and scanning only an exchange rate with pgx

[jaunt]

Hello,

Thank you for this library!

I see that the convert function takes in an exchange rate as a string to create an apd.Decimal{} for the calculation.

I'd like to store a currency conversion rate to a postgres table as a numeric and be able to scan it out, without having to use the price structure which includes currency_code which wouldn't apply in this case (all though, maybe having from and to code would make sense).

Do you have a recommendation how I might do this without having to make a new version of github.com/jackc/pgx-shopspring-decimal which uses apd instead?

Maybe if there was currency.Rate as well as currency.Amount?

// Rate stores a decimal exchange rate from and to two currencies.
type Rate struct {
	number       apd.Decimal
	fromCurrencyCode string
	toCurrencyCode string
}

I essentially want to store historical rates accurately. There is an example on this page which has a rate of 0.000000671411306566403 for example:

https://documentation.sas.com/doc/en/fmscdc/5.6/fmspag/p06qd7jikhxltgn1rotrfqopiu4y.htm