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@hsiang-c hsiang-c commented Oct 21, 2025

Which issue does this PR close?

Rationale for this change

  • Apache Spark's abs() behaves differently than DataFusion.
  • Apache Spark's ANSI-compliant dialect can be toggled by SparkConf spark.sql.ansi.enabled. When it is off, arithmetic overflow doesn't throw exception like DataFusion does.
  • Apache Spark's abs also supports ANSI interval types: YearMonthIntervalType and DayTimeIntervalType
  • DataFusion Comet can leverage it at fix: re-enable Comet abs datafusion-comet#2595

What changes are included in this PR?

  • Mimics Apache Spark v4.0.1 abs expression
  • DataFusion Spark's abs() API takes an additional flag fail_on_error if spark.sql.ansi.enabled=true at caller's side.

Are these changes tested?

  • unit tests
  • sqllogictest: test_files/spark/math/abs.slt

Are there any user-facing changes?

Yes, the abs function can be specified in the SQL.

  • Arithmetic overflow will be thrown when spark.sql.ansi.enabled=true
  • Support ANSI interval types: YearMonthIntervalType and DayTimeIntervalType

@github-actions github-actions bot added sqllogictest SQL Logic Tests (.slt) spark labels Oct 21, 2025
@hsiang-c
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cc @comphead for code review, thank you.


# abs: signed int minimal values
query IIII
select abs(c1), abs(c2), abs(c3), abs(c4) from test_nullable_integer where dataset = 'mins'
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wondering would be that easier to test like

query II
select abs(1), abs(-1)
----
1 1

?

instead of creating/dropping tables

0 0
1 1
1 1
NULL NULL
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its better to use inline query, in this example the answers and input data are out of order and it might be more difficult to read

## PySpark 3.5.5 Result: {"abs(INTERVAL '-1-1' YEAR TO MONTH)": 13, "typeof(abs(INTERVAL '-1-1' YEAR TO MONTH))": 'interval year to month', "typeof(INTERVAL '-1-1' YEAR TO MONTH)": 'interval year to month'}
#query
#SELECT abs(INTERVAL '-1-1' YEAR TO MONTH::interval year to month);
query error DataFusion error: This feature is not implemented: Unsupported SQL type INTERVAL YEAR TO MONTH
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Lets create a github ticket to fix this and refer to it in the comments in addition to the error.

Looks like abs works with intervals for Spark only

impl SparkAbs {
pub fn new() -> Self {
Self {
signature: Signature::user_defined(Volatility::Immutable),
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Suggested change
signature: Signature::user_defined(Volatility::Immutable),
signature: Signature::numeric(1, Volatility::Immutable),

Lets keep it this way for now since the PR doesn't support Intervals

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I've raised a question on the epic on how we plan to support ansi mode:

#15914 (comment)

From what I see in this PR, this is done via an extra argument to abs (though I'm not sure it's actually being passed through coerce_types correctly 🤔 )

Comment on lines +172 to +176
let fail_on_error = if args.len() == 2 {
match &args[1] {
ColumnarValue::Scalar(ScalarValue::Boolean(Some(fail_on_error))) => {
*fail_on_error
}
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Is this branch actually being tested?

Comment on lines +492 to +517
#[test]
fn test_abs_u8_scalar() {
with_fail_on_error(|fail_on_error| {
let args = ColumnarValue::Scalar(ScalarValue::UInt8(Some(u8::MAX)));
let fail_on_error_arg =
ColumnarValue::Scalar(ScalarValue::Boolean(Some(fail_on_error)));
match spark_abs(&[args, fail_on_error_arg]) {
Ok(ColumnarValue::Scalar(ScalarValue::UInt8(Some(result)))) => {
assert_eq!(result, u8::MAX);
Ok(())
}
Err(e) => {
if fail_on_error {
assert!(
e.to_string().contains("ARITHMETIC_OVERFLOW"),
"Error message did not match. Actual message: {e}"
);
Ok(())
} else {
panic!("Didn't expect error, but got: {e:?}")
}
}
_ => unreachable!(),
}
});
}
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This test design is very confusing; we can't tell if a test case is meant to return Ok or Err as it automatically does the "correct" verification for each case. This automatic way of passing the test on Err should be switched so if we have a test case that is meant to return Err, that is the only thing we check for.

Comment on lines +158 to +165
fn arithmetic_overflow_error(from_type: &str) -> DataFusionError {
ArrowError(
Box::from(arrow::error::ArrowError::ComputeError(format!(
"arithmetic overflow from {from_type}",
))),
None,
)
}
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I feel we should return a DataFusionError::Execution here instead of creating an arrow error and wrapping it in datafusion error, given the error occurs in our datafusion code

Comment on lines +119 to +121
let n = $ARRAY.as_any().downcast_ref::<$TYPE>();
match n {
Some(array) => {
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I would prefer if we unwrap n directly instead of matching on it, as we are guaranteed it would be of the correct array type; same goes for ansi_compute_op below

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3 participants