data-types.md

Data types for ledger amounts

As you can check here and here to have a better precision for a number with decimals in Postgres, the best type to use is DECIMAL/NUMERIC (numeric and decimal are the same for Postgres, check this).

I implement this with Prisma, so in the code I have the type Prisma.Decimal that under the hood use decimal.js

Problems with Prisma

You can find this problem in the file src/api/controllers/tokensExchange.ts, line 109.

I had a problem when I tried to get all the records from the daily balance account, that has a balance greater than zero for an specific account. I can't do this with a prisma normal request (with prisma client), so I have to use a raw query.

The problem with the Prisma raw query is that it is returning the wrong type for the amount in the records (it returns credit and debit as number and not Prisma.Decimal, the correct type). This is an error from Prisma. I have to convert it manually. It doesn't seems to affect so much, but I know it is not the best.

To avoid this problem I could calculate the balance when I save the record and create another column for balance, so having that, I could retrieve the daily balance with the prisma client as:

const dailyBalanceOfUsersToUpdate = await prisma.dailyBalance.findMany({
    where: {
      accountId,
      dailyId,
      balance: {
        gte: 0,
      },
    },
  });

With this I could retrieve the records with the values in the correct type.

I wanted to leave this, so I can show the problem.