appletreeisyellow opened a new issue, #24701:
URL: https://github.com/apache/datafusion/issues/24701
### Describe the bug
When a query renames a column using a DataFusion reserved name, it currently
fails with an error message that does not clearly tell the user how to resolve
the issue. For example:
```
Arrow error: Invalid argument error: Invalid comparison operation: Float64 >
Boolean
```
Even though the user's query doesn't contain a `Float64 > Boolean`
comparison, the error message is misleading.
It would be good to improve the error message so that it clearly tells the
user to choose a different column name instead of using a DF reserved name.
### To Reproduce
```sql
❯ datafusion-cli
DataFusion CLI v55.0.0
> CREATE TABLE readings(range_idx INT) AS VALUES (1);
0 row(s) fetched.
Elapsed 0.039 seconds.
-- ❌ bug reproducer
> SELECT CASE WHEN (range_idx = 1) THEN normalized_value ELSE 0.0 END AS
result
FROM (
SELECT range_idx,
CASE WHEN (range_idx = 1) THEN capped_value ELSE 0.0 END AS
normalized_value
FROM (
SELECT range_idx,
CASE WHEN (rollover_value > "__common_expr_2") THEN
rollover_value ELSE 0.0 END AS capped_value
FROM (
SELECT CASE WHEN (range_idx = 1) THEN 1.0 ELSE 0.0 END AS
"__common_expr_2",
range_idx,
CASE WHEN (range_idx = 1) THEN 2.0 ELSE 0.0 END AS
rollover_value
FROM readings
)
)
);
Arrow error: Invalid argument error: Invalid comparison operation: Float64 >
Boolean
```
```sql
-- ✅ same query, column renamed to `threshold` (not anything
`__common_expr_<n>`). Returns 2.0.
> SELECT CASE WHEN (range_idx = 1) THEN normalized_value ELSE 0.0 END AS
result
FROM (
SELECT range_idx,
CASE WHEN (range_idx = 1) THEN capped_value ELSE 0.0 END AS
normalized_value
FROM (
SELECT range_idx,
CASE WHEN (rollover_value > threshold) THEN rollover_value ELSE
0.0 END AS capped_value
FROM (
SELECT CASE WHEN (range_idx = 1) THEN 1.0 ELSE 0.0 END AS threshold,
range_idx,
CASE WHEN (range_idx = 1) THEN 2.0 ELSE 0.0 END AS
rollover_value
FROM readings
)
)
);
+--------+
| result |
+--------+
| 2.0 |
+--------+
1 row(s) fetched.
Elapsed 0.006 seconds.
```
### Expected behavior
Return a better error message, something like
```
Arrow error: Invalid argument error: __common_expr_2 is a reserved
DataFusion column name, please use another name
```
### Additional context
_No response_
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