[I] Unary negation can eliminate a required sort at the signed minimum [datafusion]

["Amogh-2404 (via GitHub)" <gi...@apache.org>]

Amogh-2404 opened a new issue, #24683:
URL: https://github.com/apache/datafusion/issues/24683

   ### Describe the bug
   
   `NegativeExpr::get_properties` always reverses its child ordering. Integer array negation uses wrapping arithmetic, so negating the minimum signed value returns the same value and is not monotonic across the full domain.
   
   The incorrect ordering claim can remove a required `SortExec` and return rows in the wrong order.
   
   ### To Reproduce
   
   ```sql
   SELECT i, -i AS n
   FROM (
     SELECT i
     FROM (
       VALUES
         (CAST(-128 AS TINYINT)),
         (CAST(-1 AS TINYINT)),
         (CAST(0 AS TINYINT)),
         (CAST(1 AS TINYINT))
     ) AS v(i)
     ORDER BY i DESC
     LIMIT 4
   ) AS t
   ORDER BY n ASC;
   ```
   
   Current result:
   
   ```text
   1    -1
   0     0
   -1    1
   -128 -128
   ```
   
   Expected result:
   
   ```text
   -128 -128
   1    -1
   0     0
   -1    1
   ```
   
   ### Expected behavior
   
   DataFusion should retain the outer sort unless it can prove that the signed minimum is outside the input range.
   
   ### Additional context
   
   This is a pre-existing single-negation issue found while working on #24668. A fix should retain safe ordering for exact widening casts such as `Int32` to `Int64`, and for wrapping double negation on unbounded integer streams.


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Re: [I] Unary negation can eliminate a required sort at the signed minimum [datafusion]

["kosiew (via GitHub)" <gi...@apache.org>]

kosiew closed issue #24683: Unary negation can eliminate a required sort at the signed minimum
URL: https://github.com/apache/datafusion/issues/24683


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