karlovnv opened a new issue, #10433:
URL: https://github.com/apache/datafusion/issues/10433
### Is your feature request related to a problem or challenge?
Consider we have huge data source consists of many record batches.
Now it's impossible to get last recent N rows without full scan:
``` sql
SELECT * FROM Events
ORDER BE event_time DESC
LIMIT 1000
```
The query above will do full scan from the starting row, but TableProvider
may know that it needed to provide only last record batches (or latest parquet
files in folder).
### Describe the solution you'd like
Now we have filter and limit in TableProvider::scan:
``` rust
async fn scan(
&self,
state: &SessionState,
projection: Option<&Vec<usize>>,
// filters and limit can be used here to inject some push-down
operations if needed
filters: &[Expr],
limit: Option<usize>,
) -> Result<Arc<dyn ExecutionPlan>> {
```
Let's add SortExpression as well to push it down or just consider:
``` rust
async fn scan(
&self,
state: &SessionState,
projection: Option<&Vec<usize>>,
// filters and limit can be used here to inject some push-down
operations if needed
filters: &[Expr],
// sort expression
sorting: &[Expr],
limit: Option<usize>,
) -> Result<Arc<dyn ExecutionPlan>> {
```
### Describe alternatives you've considered
_No response_
### Additional context
_No response_
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