[jira] [Created] (SPARK-27604) Enhance constant and constraint propagation

["Peter Toth (JIRA)" <ji...@apache.org>]

Peter Toth created SPARK-27604:
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             Summary: Enhance constant and constraint propagation
                 Key: SPARK-27604
                 URL: https://issues.apache.org/jira/browse/SPARK-27604
             Project: Spark
          Issue Type: Improvement
          Components: SQL
    Affects Versions: 3.0.0
            Reporter: Peter Toth


There is some room for improvement in terms of how we can use constraints to simplify expressions and maybe what new expressions we can infer.

Here are some examples what the current implementation can do in terms of expression simplification:
{code:java}
SELECT * FROM table WHERE i = 5 AND j = i + 3      =>  SELECT * FROM table WHERE i = 5 AND j = 8
{code}

And here are some that it could with some improvement:
{code:java}
SELECT * FROM table WHERE i <= 5 AND i = 5         =>  SELECT * FROM table WHERE i = 5
SELECT * FROM table WHERE i < j AND ... AND i = j  =>  SELECT * FROM table WHERE false{code}

I also think that `ConstantPropagation` and `InferFiltersFromConstraints` functionality somewhat overlaps and with some refactoring we could come up with a better solution.




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