zhuqi-lucas opened a new pull request, #13788:
URL: https://github.com/apache/datafusion/pull/13788

   ## Which issue does this PR close?
   
   Closes [#.](https://github.com/apache/datafusion/issues/13745)
   
   ## Rationale for this change
   We always limit the partition file even with filter before limit, so it will 
return the wrong file group numbers for us to filter the data before the final 
limit.
   
   Fix way, we should not limit the partition files when we have filter already 
with limit.
   
   
   ## What changes are included in this PR?
   
   
   ## Are these changes tested?
   
   Testing code with generating files.
   
   ```
   #[tokio::main]
   pub async fn main() -> Result<()> {
       let output_dir = "/tmp/test_parquet_data";
       let num_files = 120; // Number of Parquet files
       let rows_per_file = 200; // Number of rows per Parquet file
   
       // Generate the dataset
       generate_test_data(output_dir, num_files, rows_per_file);
       println!("Generated {} Parquet files with {} rows each", num_files, 
rows_per_file);
   
       let file_path = "/tmp/test_parquet_data/part-119.parquet"; // 最后一个文件
       let file = File::open(file_path).unwrap();
       let parquet_reader = SerializedFileReader::new(file).unwrap();
       let mut iter = parquet_reader.get_row_iter(None).unwrap();
   
       while let Some(record) = iter.next() {
           println!("{:?}", record);
       }
   
   
       let mut parquet_options = ParquetReadOptions::new();
       parquet_options = parquet_options.parquet_pruning(true);
   
       let mut config = SessionConfig::new();
       config.options_mut().execution.parquet.pushdown_filters = true;
   
       let state = SessionStateBuilder::new().with_config(config).build();
       let ctx = SessionContext::from(state);
   
       let mut df = ctx
           .read_parquet(output_dir, parquet_options.clone())
           .await
           .unwrap();
   
       df = df
           .filter(col("a").eq(lit(
               "23asdas23",
           )))
           .unwrap();
   
       df = df.limit(0, Some(1)).unwrap();
   
       let batch = df.collect().await.unwrap();
   
   
   
       println!("{:?}", batch);
   
       Ok(())
   }
   
   
   fn generate_test_data(output_dir: &str, num_files: usize, rows_per_file: 
usize) {
       // Define the schema
       let schema = Arc::new(Schema::new(vec![
           Field::new("a", DataType::Utf8, false),
           Field::new("b", DataType::Int32, false),
       ]));
   
       for file_index in 0..num_files {
           // Generate data for this file
           let mut a_values = Vec::new();
           let mut b_values = Vec::new();
   
           for row_index in 0..rows_per_file {
               // Fill in rows
               if file_index == num_files - 1 && row_index == rows_per_file / 2 
{
                   // Add the target row deep in the dataset
                   a_values.push("23asdas23".to_string());
                   b_values.push(999);
               } else {
                   a_values.push(format!("random_{}_{}", file_index, 
row_index));
                   b_values.push((file_index * rows_per_file + row_index) as 
i32);
               }
           }
   
           // Create Arrow arrays
           let a_array = Arc::new(StringArray::from(a_values)) as Arc<dyn 
arrow::array::Array>;
           let b_array = Arc::new(Int32Array::from(b_values)) as Arc<dyn 
arrow::array::Array>;
   
           // Create a record batch
           let batch = RecordBatch::try_new(schema.clone(), vec![a_array, 
b_array]).unwrap();
   
           // Write to a Parquet file
           let file_path = format!("{}/part-{}.parquet", output_dir, 
file_index);
           let file = File::create(file_path).unwrap();
           let props = WriterProperties::builder().build();
           let mut writer = ArrowWriter::try_new(file, schema.clone(), 
Some(props)).unwrap();
           writer.write(&batch).unwrap();
           writer.close().unwrap();
       }
   }
   ```
   
   
   
   After this PR, the testing will  print the right value instead of the empty 
value.
   
   println!("{:?}", batch); 
   
   ## Are there any user-facing changes?
   
   No


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