Trait parquet::file::reader::RowGroupReader

[+] Show declaration

pub trait RowGroupReader {
    fn metadata(&self) -> RowGroupMetaDataPtr;
    fn num_columns(&self) -> usize;
    fn get_column_page_reader(&self, i: usize) -> Result<Box<PageReader>>;
    fn get_column_reader(&self, i: usize) -> Result<ColumnReader>;
    fn get_row_iter(&self, projection: Option<SchemaType>) -> Result<RowIter>;
}

[−] Expand description

Parquet row group reader API. With this, user can get metadata information about the row group, as well as readers for each individual column chunk.

Required Methods

fn metadata(&self) -> RowGroupMetaDataPtr[−]

Get metadata information about this row group.

fn num_columns(&self) -> usize[−]

Get the total number of column chunks in this row group.

fn get_column_page_reader(&self, i: usize) -> Result<Box<PageReader>>[−]

Get page reader for the ith column chunk.

fn get_column_reader(&self, i: usize) -> Result<ColumnReader>[−]

Get value reader for the ith column chunk.

fn get_row_iter(&self, projection: Option<SchemaType>) -> Result<RowIter>[−]

Get iterator of Rows from this row group.

Projected schema can be a subset of or equal to the file schema, when it is None, full file schema is assumed.

Implementors

impl<R: 'static + ParquetReader> RowGroupReader for SerializedRowGroupReader<R>

[−]

fn metadata(&self) -> RowGroupMetaDataPtr

fn num_columns(&self) -> usize

fn get_column_page_reader(&self, i: usize) -> Result<Box<PageReader>>

fn get_column_reader(&self, i: usize) -> Result<ColumnReader>

fn get_row_iter(&self, projection: Option<SchemaType>) -> Result<RowIter>