prestodb/presto · error · ArithmeticException

Division by zero

Error message

Division by zero

What it means

throwDivisionByZeroException is the central helper raised whenever a DECIMAL division or modulo has a zero divisor; it fires from the unscaled-128 arithmetic paths when users execute decimal division by zero.

Source

Thrown at presto-common/src/main/java/com/facebook/presto/common/type/UnscaledDecimal128Arithmetic.java:1579

        long remainder = getLong(decimal, 1);
        long high = remainder / divisor;
        remainder %= divisor;

        remainder = (getInt(decimal, 1) & LONG_MASK) + (remainder << 32);
        int z1 = (int) (remainder / divisor);
        remainder %= divisor;

        remainder = (getInt(decimal, 0) & LONG_MASK) + (remainder << 32);
        int z0 = (int) (remainder / divisor);

        pack(result, z0, z1, high, isNegative(decimal));
        return (int) (remainder % divisor);
    }

    private static void throwDivisionByZeroException()
    {
        throw new ArithmeticException("Division by zero");
    }

    private static void multiplyShiftDestructive(Slice decimal, Slice multiplier, int rightShifts)
    {
        int[] product = new int[NUMBER_OF_INTS * 2];
        Slice multiplicationResult = Slices.wrappedIntArray(product);
        multiply256(decimal, multiplier, multiplicationResult);
        shiftRightArray8(product, rightShifts, decimal);
    }

    private static void setNegative(Slice decimal, boolean negative)
    {
        setRawInt(decimal, SIGN_INT_INDEX, getInt(decimal, SIGN_INT_INDEX) | (negative ? SIGN_INT_MASK : 0));
    }

    private static void setNegativeInt(Slice decimal, int v3, boolean negative)
    {
        if (v3 < 0) {

View on GitHub (pinned to 55bb57d202)

Solutions

1. Filter or NULL out zero divisors before the division
2. Use NULLIF(divisor, 0) in SQL to avoid the divide-by-zero path

When it happens

Trigger: Thrown at presto-common/src/main/java/com/facebook/presto/common/type/UnscaledDecimal128Arithmetic.java:1579 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/41692ae64dae2ef8. Report an issue: GitHub.