Negative decimals less than 1 erroneously converted to positive

[timkpaine]

#[test]
fn negative_decimal_small() {
    let actual = decimal_text_to_i128(b"-0.1", 5);
   assert_eq!(-10000, actual);
}

assertion `left == right` failed
  left: -10000
 right: 10000

After pacman82/arrow-odbc@cc5d45d, this seems to break both arrow-odbc and arrow-odbc-py fairly seriously (all negative decimals with magnitude less than 1 converted to positive). The bug is fairly clear:

    let (mut high, num_digits_high) = i128::from_radix_10_signed(text);

It is assumed high will have a sign, but if its 0 it will not preserve the negative.

[pacman82]

fairly seriously

True I'll try to release a fix after work

[pacman82]

merged your PR released odbc-api and downstream artefacts arrow-odbc and odbc2parquet. Short on time, but thanks for catching this.