Struct ParquetOptions

pub struct ParquetOptions {

    pub enable_page_index: bool,
    pub pruning: bool,
    pub skip_metadata: bool,
    pub metadata_size_hint: Option<usize>,
    pub pushdown_filters: bool,
    pub reorder_filters: bool,
    pub schema_force_view_types: bool,
    pub binary_as_string: bool,
    pub data_pagesize_limit: usize,
    pub write_batch_size: usize,
    pub writer_version: String,
    pub compression: Option<String>,
    pub dictionary_enabled: Option<bool>,
    pub dictionary_page_size_limit: usize,
    pub statistics_enabled: Option<String>,
    pub max_statistics_size: Option<usize>,
    pub max_row_group_size: usize,
    pub created_by: String,
    pub column_index_truncate_length: Option<usize>,
    pub data_page_row_count_limit: usize,
    pub encoding: Option<String>,
    pub bloom_filter_on_read: bool,
    pub bloom_filter_on_write: bool,
    pub bloom_filter_fpp: Option<f64>,
    pub bloom_filter_ndv: Option<u64>,
    pub allow_single_file_parallelism: bool,
    pub maximum_parallel_row_group_writers: usize,
    pub maximum_buffered_record_batches_per_stream: usize,
}

Options for reading and writing parquet files

See also: SessionConfig

Fields

enable_page_index: bool

(reading) If true, reads the Parquet data page level metadata (the Page Index), if present, to reduce the I/O and number of rows decoded.

pruning: bool

(reading) If true, the parquet reader attempts to skip entire row groups based on the predicate in the query and the metadata (min/max values) stored in the parquet file

skip_metadata: bool

(reading) If true, the parquet reader skip the optional embedded metadata that may be in the file Schema. This setting can help avoid schema conflicts when querying multiple parquet files with schemas containing compatible types but different metadata

metadata_size_hint: Option<usize>

(reading) If specified, the parquet reader will try and fetch the last size_hint bytes of the parquet file optimistically. If not specified, two reads are required: One read to fetch the 8-byte parquet footer and another to fetch the metadata length encoded in the footer

pushdown_filters: bool

(reading) If true, filter expressions are be applied during the parquet decoding operation to reduce the number of rows decoded. This optimization is sometimes called “late materialization”.

reorder_filters: bool

(reading) If true, filter expressions evaluated during the parquet decoding operation will be reordered heuristically to minimize the cost of evaluation. If false, the filters are applied in the same order as written in the query

schema_force_view_types: bool

(reading) If true, parquet reader will read columns of Utf8/Utf8Large with Utf8View, and Binary/BinaryLarge with BinaryView.

binary_as_string: bool

(reading) If true, parquet reader will read columns of Binary/LargeBinary with Utf8, and BinaryView with Utf8View.

Parquet files generated by some legacy writers do not correctly set the UTF8 flag for strings, causing string columns to be loaded as BLOB instead.

data_pagesize_limit: usize

(writing) Sets best effort maximum size of data page in bytes

write_batch_size: usize

(writing) Sets write_batch_size in bytes

writer_version: String

(writing) Sets parquet writer version valid values are “1.0” and “2.0”

compression: Option<String>

(writing) Sets default parquet compression codec. Valid values are: uncompressed, snappy, gzip(level), lzo, brotli(level), lz4, zstd(level), and lz4_raw. These values are not case sensitive. If NULL, uses default parquet writer setting

Note that this default setting is not the same as the default parquet writer setting.

dictionary_enabled: Option<bool>

(writing) Sets if dictionary encoding is enabled. If NULL, uses default parquet writer setting

dictionary_page_size_limit: usize

(writing) Sets best effort maximum dictionary page size, in bytes

statistics_enabled: Option<String>

(writing) Sets if statistics are enabled for any column Valid values are: “none”, “chunk”, and “page” These values are not case sensitive. If NULL, uses default parquet writer setting

max_statistics_size: Option<usize>

(writing) Sets max statistics size for any column. If NULL, uses default parquet writer setting

max_row_group_size: usize

(writing) Target maximum number of rows in each row group (defaults to 1M rows). Writing larger row groups requires more memory to write, but can get better compression and be faster to read.

created_by: String

(writing) Sets “created by” property

column_index_truncate_length: Option<usize>

(writing) Sets column index truncate length

data_page_row_count_limit: usize

(writing) Sets best effort maximum number of rows in data page

encoding: Option<String>

(writing) Sets default encoding for any column. Valid values are: plain, plain_dictionary, rle, bit_packed, delta_binary_packed, delta_length_byte_array, delta_byte_array, rle_dictionary, and byte_stream_split. These values are not case sensitive. If NULL, uses default parquet writer setting

bloom_filter_on_read: bool

(writing) Use any available bloom filters when reading parquet files

bloom_filter_on_write: bool

(writing) Write bloom filters for all columns when creating parquet files

bloom_filter_fpp: Option<f64>

(writing) Sets bloom filter false positive probability. If NULL, uses default parquet writer setting

bloom_filter_ndv: Option<u64>

(writing) Sets bloom filter number of distinct values. If NULL, uses default parquet writer setting

allow_single_file_parallelism: bool

(writing) Controls whether DataFusion will attempt to speed up writing parquet files by serializing them in parallel. Each column in each row group in each output file are serialized in parallel leveraging a maximum possible core count of n_filesn_row_groupsn_columns.

maximum_parallel_row_group_writers: usize

(writing) By default parallel parquet writer is tuned for minimum memory usage in a streaming execution plan. You may see a performance benefit when writing large parquet files by increasing maximum_parallel_row_group_writers and maximum_buffered_record_batches_per_stream if your system has idle cores and can tolerate additional memory usage. Boosting these values is likely worthwhile when writing out already in-memory data, such as from a cached data frame.

maximum_buffered_record_batches_per_stream: usize

(writing) By default parallel parquet writer is tuned for minimum memory usage in a streaming execution plan. You may see a performance benefit when writing large parquet files by increasing maximum_parallel_row_group_writers and maximum_buffered_record_batches_per_stream if your system has idle cores and can tolerate additional memory usage. Boosting these values is likely worthwhile when writing out already in-memory data, such as from a cached data frame.

Trait Implementations

impl Clone for ParquetOptions

fn clone(&self) -> ParquetOptions

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl ConfigField for ParquetOptions

fn set(&mut self, key: &str, value: &str) -> Result<()>

fn visit<V: Visit>( &self, v: &mut V, key_prefix: &str, _description: &'static str, )

impl Debug for ParquetOptions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ParquetOptions

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for ParquetOptions

fn eq(&self, other: &ParquetOptions) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for ParquetOptions