Module arrow2::io::parquet::read

Available on crate feature io_parquet only.

APIs to read from Parquet format.

Re-exports

• pub use schema::infer_schema;
• pub use parquet2::fallible_streaming_iterator;

Modules

• indexes
  API to perform page-level filtering (also known as indexes)
• schema
  APIs to handle Parquet <-> Arrow schemas.
• statistics
  APIs exposing parquet2’s statistics as arrow’s statistics.

Structs

• BasicDecompressor
  A FallibleStreamingIterator that decompresses CompressedPage into DataPage.
• ColumnChunkMetaData
  Metadata for a column chunk.
• ColumnDescriptor
  A descriptor for leaf-level primitive columns. This encapsulates information such as definition and repetition levels and is used to re-assemble nested data.
• CompressedDataPage
  A CompressedDataPage is compressed, encoded representation of a Parquet data page. It holds actual data and thus cloning it is expensive.
• Decompressor
  Decompressor that allows re-using the page buffer of PageIterator.
• FileMetaData
  Metadata for a Parquet file.
• FileReader
  An iterator of Chunks coming from row groups of a parquet file.
• NestedState
  The state of nested data types.
• PageReader
  A fallible Iterator of CompressedDataPage. This iterator reads pages back to back until all pages have been consumed. The pages from this iterator always have None crate::page::CompressedDataPage::selected_rows() since filter pushdown is not supported without a pre-computed page index.
• ReadColumnIterator
  A MutStreamingIterator of pre-read column chunks
• RowGroupDeserializer
  An Iterator of Chunk that (dynamically) adapts a vector of iterators of Array into an iterator of Chunk.
• RowGroupMetaData
  Metadata for a row group.
• RowGroupReader
  An [Iterator<Item=RowGroupDeserializer>] from row groups of a parquet file.
• StructIterator
  An iterator adapter over NestedArrayIter assumed to be encoded as Struct arrays

Enums

• DataPageHeader
• GroupLogicalType
• InitNested
  The initial info of nested data types.
• Page
  A Page is an uncompressed, encoded representation of a Parquet page. It may hold actual data and thus cloning it may be expensive.
• ParquetError
  Errors generated by this crate
• ParquetTimeUnit
• ParquetType
  Representation of a Parquet type describing primitive and nested fields, including the top-level schema of the parquet file.
• PhysicalType
  The set of all physical types representable in Parquet
• PrimitiveConvertedType
• PrimitiveLogicalType
• State
  State of MutStreamingIterator.

Traits

• FallibleStreamingIterator
  A fallible, streaming iterator.
• MutStreamingIterator
  A special kind of fallible streaming iterator where advance consumes the iterator.
• Pages
  Trait describing a FallibleStreamingIterator of Page

Functions

• _read_columns_indexes
  Reads the column indexes of all ColumnChunkMetaData and deserializes them into Index. Returns an empty vector if indexes are not available
• _read_metadata
  Reads a FileMetaData from the reader, located at the end of the file.
• _read_metadata_async
  Asynchronously reads the files’ metadata
• column_iter_to_arrays
  An iterator adapter that maps multiple iterators of Pages into an iterator of Arrays.
• create_list
  Creates a new ListArray or FixedSizeListArray.
• create_map
  Creates a new MapArray.
• decompress
  Decompresses the page, using buffer for decompression. If page.buffer.len() == 0, there was no decompression and the buffer was moved. Else, decompression took place.
• get_column_iterator
  Returns a ColumnIterator of column chunks corresponding to field.
• get_field_columns
  Returns all ColumnChunkMetaData associated to field_name. For non-nested parquet types, this returns a single column
• get_field_pages
  Returns all ColumnChunkMetaData associated to field_name. For non-nested parquet types, this returns a single column
• get_page_iterator
  Creates a new iterator of compressed pages.
• get_page_stream
  Returns a stream of compressed data pages
• init_nested
  Initialize NestedState from &[InitNested].
• int96_to_i64_ns
• n_columns
  Returns the number of (parquet) columns that a DataType contains.
• read_columns
  Reads all columns that are part of the parquet field field_name
• read_columns_async
  Reads all columns that are part of the parquet field field_name
• read_columns_many
  Returns a vector of iterators of Array (ArrayIter) corresponding to the top level parquet fields whose name matches fields’s names.
• read_columns_many_async
  Returns a vector of iterators of Array corresponding to the top level parquet fields whose name matches fields’s names.
• read_metadata
  Reads parquets’ metadata syncronously.
• read_metadata_async
  Reads parquets’ metadata asynchronously.
• read_pages_locations
  Read [PageLocation]s from the ColumnChunkMetaDatas. Returns an empty vector if indexes are not available
• to_deserializer
  Converts a vector of columns associated with the parquet field whose name is Field to an iterator of Array, ArrayIter of chunk size chunk_size.

Type Aliases

• ArrayIter
  Type def for a sharable, boxed dyn Iterator of arrays
• NestedArrayIter
  Type def for a sharable, boxed dyn Iterator of NestedStates and arrays
• PageFilter
  Type declaration for a page filter