tv42 opened a new issue, #8909:
URL: https://github.com/apache/arrow-datafusion/issues/8909
### Describe the bug
Datafusion evaluates `CASE ... WHEN ... THEN` expressions even for non-true
branches, and bubbles up runtime errors from them.
This is wrong because the `CASE` could be explicitly protecting against the
divide-by-zero case, and differs from other sql engines.
### To Reproduce
```console
❯ SELECT CASE 1 WHEN 2 THEN 42/0 END;
Optimizer rule 'simplify_expressions' failed
caused by
Arrow error: Divide by zero error
```
### Expected behavior
I expected the `CASE` to evaluate to `NULL`, as none of its `WHEN` branches
were true and it did not have an `ELSE`.
Compare to SQLite:
```console
sqlite> .nullvalue NULL
sqlite> SELECT CASE 1 WHEN 2 THEN 42/0 END;
NULL
```
Compare to Postgres:
```console
postgres=# \pset null 'NULL'
Null display is "NULL".
postgres=# SELECT CASE 1 WHEN 2 THEN 42/0 END;
case
------
NULL
(1 row)
```
### Additional context
_No response_
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