Struct polars::prelude::ParquetWriter

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pub struct ParquetWriter<W> { /* private fields */ }

Expand description

Write a DataFrame to parquet format

Implementations

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impl<W> ParquetWriter<W> where
W: Write,

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pub fn new(writer: W) -> ParquetWriter<W> where
W: Write,

Create a new writer

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pub fn with_compression(
self,
compression: CompressionOptions
) -> ParquetWriter<W>

Set the compression used. Defaults to Lz4Raw.

The default compression Lz4Raw has very good performance, but may not yet been supported by older readers. If you want more compatability guarantees, consider using Snappy.

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pub fn with_statistics(self, statistics: bool) -> ParquetWriter<W>

Compute and write statistic

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pub fn with_row_group_size(self, size: Option<usize>) -> ParquetWriter<W>

Set the row group size during writing. This can reduce memory pressure and improve writing performance.

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pub fn finish(self, df: &mut DataFrame) -> Result<(), PolarsError>

Write the given DataFrame in the the writer W.

Auto Trait Implementations

impl<W> RefUnwindSafe for ParquetWriter<W> where
W: RefUnwindSafe,

impl<W> Send for ParquetWriter<W> where
W: Send,

impl<W> Sync for ParquetWriter<W> where
W: Sync,

impl<W> Unpin for ParquetWriter<W> where
W: Unpin,

impl<W> UnwindSafe for ParquetWriter<W> where
W: UnwindSafe,

Blanket Implementations

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impl<T> Any for T where
T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

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impl<T> Borrow<T> for T where
T: ?Sized,

const: unstable · source

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

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impl<T> BorrowMut<T> for T where
T: ?Sized,

const: unstable · source

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

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impl<T> From<T> for T

const: unstable · source

fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into for T where
U: From<T>,

const: unstable · source

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

impl<T> Pointable for T

const ALIGN: usize = mem::align_of::<T>()

The alignment of pointer.

type Init = T

The type for initializers.

unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more

unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

Mutably dereferences the given pointer. Read more

unsafe fn drop(ptr: usize)

Drops the object pointed to by the given pointer. Read more

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impl<T, U> TryFrom for T where
U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

const: unstable · source

fn try_from(value: U) -> Result<T, <T as TryFrom>::Error>

Performs the conversion.

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impl<T, U> TryInto for T where
U: TryFrom<T>,

type Error = >::Error

The type returned in the event of a conversion error.

const: unstable · source

fn try_into(self) -> Result<U, >::Error>

Performs the conversion.

Struct polars::prelude::ParquetWriter

Implementations

impl<W> ParquetWriter<W> where
W: Write,

pub fn new(writer: W) -> ParquetWriter<W> where
W: Write,

pub fn with_compression(
self,
compression: CompressionOptions
) -> ParquetWriter<W>

pub fn with_statistics(self, statistics: bool) -> ParquetWriter<W>

pub fn with_row_group_size(self, size: Option<usize>) -> ParquetWriter<W>

pub fn finish(self, df: &mut DataFrame) -> Result<(), PolarsError>

Auto Trait Implementations

impl<W> RefUnwindSafe for ParquetWriter<W> where
W: RefUnwindSafe,

impl<W> Send for ParquetWriter<W> where
W: Send,

impl<W> Sync for ParquetWriter<W> where
W: Sync,

impl<W> Unpin for ParquetWriter<W> where
W: Unpin,

impl<W> UnwindSafe for ParquetWriter<W> where
W: UnwindSafe,

Blanket Implementations

impl<T> Any for T where
T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for T where
T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for T where
T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T> From<T> for T

fn from(t: T) -> T

impl<T, U> Into<U> for T where
U: From<T>,

fn into(self) -> U

impl<T> Pointable for T

const ALIGN: usize = mem::align_of::<T>()

type Init = T

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

unsafe fn drop(ptr: usize)

impl<T, U> TryFrom<U> for T where
U: Into<T>,

type Error = Infallible

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

impl<T, U> TryInto<U> for T where
U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

impl<V, T> VZip<V> for T where
V: MultiLane<T>,

fn vzip(self) -> V

Struct polars::prelude::ParquetWriter

Implementations

impl<W> ParquetWriter<W> where W: Write,

pub fn new(writer: W) -> ParquetWriter<W> where W: Write,

pub fn with_compression( self, compression: CompressionOptions) -> ParquetWriter<W>

pub fn with_statistics(self, statistics: bool) -> ParquetWriter<W>

pub fn with_row_group_size(self, size: Option<usize>) -> ParquetWriter<W>

pub fn finish(self, df: &mut DataFrame) -> Result<(), PolarsError>

Auto Trait Implementations

impl<W> RefUnwindSafe for ParquetWriter<W> where W: RefUnwindSafe,

impl<W> Send for ParquetWriter<W> where W: Send,

impl<W> Sync for ParquetWriter<W> where W: Sync,

impl<W> Unpin for ParquetWriter<W> where W: Unpin,

impl<W> UnwindSafe for ParquetWriter<W> where W: UnwindSafe,

Blanket Implementations

impl<T> Any for T where T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for T where T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for T where T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T> From<T> for T

fn from(t: T) -> T

impl<T, U> Into<U> for T where U: From<T>,

fn into(self) -> U

impl<T> Pointable for T

const ALIGN: usize = mem::align_of::<T>()

type Init = T

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

unsafe fn drop(ptr: usize)

impl<T, U> TryFrom<U> for T where U: Into<T>,

type Error = Infallible

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

impl<T, U> TryInto<U> for T where U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

impl<V, T> VZip<V> for T where V: MultiLane<T>,

fn vzip(self) -> V

impl<W> ParquetWriter<W> where
W: Write,

pub fn new(writer: W) -> ParquetWriter<W> where
W: Write,

pub fn with_compression(
self,
compression: CompressionOptions
) -> ParquetWriter<W>

impl<W> RefUnwindSafe for ParquetWriter<W> where
W: RefUnwindSafe,

impl<W> Send for ParquetWriter<W> where
W: Send,

impl<W> Sync for ParquetWriter<W> where
W: Sync,

impl<W> Unpin for ParquetWriter<W> where
W: Unpin,

impl<W> UnwindSafe for ParquetWriter<W> where
W: UnwindSafe,

impl<T> Any for T where
T: 'static + ?Sized,

impl<T> Borrow<T> for T where
T: ?Sized,

impl<T> BorrowMut<T> for T where
T: ?Sized,

impl<T, U> Into<U> for T where
U: From<T>,

impl<T, U> TryFrom<U> for T where
U: Into<T>,

impl<T, U> TryInto<U> for T where
U: TryFrom<T>,

impl<V, T> VZip<V> for T where
V: MultiLane<T>,