andygrove opened a new issue, #11570:
URL: https://github.com/apache/datafusion/issues/11570
### Is your feature request related to a problem or challenge?
A common usage of `CASE WHEN` (particularly in the TPC-DS benchmark) is to
protect against divide by zero errors. For example:
``sql
CASE WHEN y > 0 THEN x / y ELSE null END
```
The `CaseExpr` implementation is quite expensive and we could replace this
whole expression with a divide kernel that returns null if the right hand side
is zero (Rust has a `div_checked` function that already provides this
functionality).
arrow-rs already has the following code in `arrow-array/src/arithmetic.rs`,
which is really close to what we need. I think we just need a version that
returns an `Option::None` instead of an `Err`.
```rust
#[inline]
fn div_checked(self, rhs: Self) -> Result<Self, ArrowError> {
if rhs.is_zero() {
Err(ArrowError::DivideByZero)
} else {
self.checked_div(rhs).ok_or_else(|| {
ArrowError::ComputeError(format!(
"Overflow happened on: {:?} / {:?}",
self, rhs
))
})
}
}
```
### Describe the solution you'd like
_No response_
### Describe alternatives you've considered
_No response_
### Additional context
_No response_
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