mustafasrepo opened a new issue, #6510:
URL: https://github.com/apache/arrow-datafusion/issues/6510
### Describe the bug
Assume we have a table with single column `ts` such as below
|a|
|----|
|1|
|2|
|3|
|4|
when I run the query below on this table
```sql
SELECT * EXCEPT(a)
FROM table1
```
It gives `Error: Context("push_down_projection", Internal("Optimizer rule
'push_down_projection' failed, due to generate a different schema, original
schema: DFSchema { fields: [], metadata: {} }, new schema: DFSchema { fields:
[DFField { qualifier: Some(Bare { table: \"table1\" }), field: Field { name:
\"a\", data_type: Int32, nullable: true, dict_id: 0, dict_is_ordered: false,
metadata: {} } }], metadata: {} }"))` error.
However, assume we have an empty table with no columns named `empty_table`.
Query below works
```sql
SELECT *
FROM empty_table
```
So I don't think bug is related to showing empty columns, but I am not sure.
### To Reproduce
You can use test below to reproduce problem
```rust
#[tokio::test]
async fn test_exclude_error() -> Result<()> {
let config = SessionConfig::new()
.with_target_partitions(1);
let ctx = SessionContext::with_config(config);
ctx.sql("CREATE TABLE table1 (
a INT,
) as VALUES
(1),
(2),
(3),
(4)").await?;
let sql = "SELECT * EXCEPT(a)
FROM table1";
let msg = format!("Creating logical plan for '{sql}'");
let dataframe = ctx.sql(sql).await.expect(&msg);
let physical_plan = dataframe.create_physical_plan().await?;
let batches = collect(physical_plan, ctx.task_ctx()).await?;
print_batches(&batches)?;
Ok(())
}
```
Test below shows that datafusion has no problem with showing 0 columns.
```rust
#[tokio::test]
async fn test_empty_table() -> Result<()> {
let config = SessionConfig::new()
.with_target_partitions(1);
let ctx = SessionContext::with_config(config);
ctx.sql("CREATE TABLE empty_table ()").await?;
let sql = "SELECT *
FROM empty_table";
let msg = format!("Creating logical plan for '{sql}'");
let dataframe = ctx.sql(sql).await.expect(&msg);
let physical_plan = dataframe.create_physical_plan().await?;
let batches = collect(physical_plan, ctx.task_ctx()).await?;
print_batches(&batches)?;
Ok(())
}
```
### Expected behavior
I expect first query to run successfully
### Additional context
_No response_
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