alamb opened a new issue, #11594:
URL: https://github.com/apache/datafusion/issues/11594
### Is your feature request related to a problem or challenge?
DataFusion will simplify expressions like this: `i + (1 + 2)` => `i + 3`
However, it will not simplify `i + 1 + 2` (remains `i + 1 + 2`)
You can see this in the explain plans
```
> explain select column1 + (1 + 2) from values (100);
+---------------+-----------------------------------------------------------------------+
| plan_type | plan
|
+---------------+-----------------------------------------------------------------------+
| logical_plan | Projection: column1 + Int64(3) AS column1 + Int64(1) +
Int64(2) |
| | Values: (Int64(100))
|
| physical_plan | ProjectionExec: expr=[column1@0 + 3 as column1 + Int64(1)
+ Int64(2)] | <-- computed expression is `column1@0 + 3`
| | ValuesExec
|
| |
|
+---------------+-----------------------------------------------------------------------+
2 row(s) fetched.
Elapsed 0.013 seconds.
> explain select column1 + 1 + 2 from values (100);
+---------------+---------------------------------------------------------------------------+
| plan_type | plan
|
+---------------+---------------------------------------------------------------------------+
| logical_plan | Projection: column1 + Int64(1) + Int64(2)
|
| | Values: (Int64(100))
|
| physical_plan | ProjectionExec: expr=[column1@0 + 1 + 2 as column1 +
Int64(1) + Int64(2)] | <-- expression is STILL `column1@0 + 1 + 2`
| | ValuesExec
|
| |
|
+---------------+---------------------------------------------------------------------------+
2 row(s) fetched.
Elapsed 0.002 seconds.
```
@timsaucer has identified the problem
> I don’t have time to look through the code right now, but I would guess
the operations happen left to right when you don’t have parentheses to indicate
order. So the second would be equivalent to (col(“i”) + lit(1)) + lit(2). That
is, would guess it isn’t checking for associativity of operations.
So in this case `i + 1 + 2` is parsed as `(i + 1) + 2` and since `(i + 1)`
can't be reduced, the entire expression isn't either
### Describe the solution you'd like
It would be nice to properly support this simplification
### Describe alternatives you've considered
_No response_
### Additional context
Came up on discord:
https://discord.com/channels/885562378132000778/1166447479609376850/1264325499971436594
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