RecordBatchReader classes

RecordBatchFileReader and RecordBatchStreamReader are interfaces for generating record batches from different input sources.

Factory

The RecordBatchFileReader$create() and RecordBatchStreamReader$create() factory methods instantiate the object and take a single argument, named according to the class:

• file A character file name, raw vector, or Arrow file connection object (e.g. RandomAccessFile).

• stream A raw vector, Buffer, or InputStream.

Methods

• $read_next_batch(): Returns a RecordBatch

• $schema(): Returns a Schema

• $batches(): Returns a list of RecordBatches

• $get_batch(i): For RecordBatchFileReader, return a particular batch by an integer index.

• $num_record_batches(): For RecordBatchFileReader, see how many batches are in the file.

Super class

arrow::Object -> RecordBatchReader

Methods

Public methods

• RecordBatchReader$read_next_batch()

• RecordBatchReader$clone()

Inherited methods

• arrow::Object$initialize()

• arrow::Object$pointer()

• arrow::Object$print()

• arrow::Object$set_pointer()

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Method read_next_batch()

Usage

RecordBatchReader$read_next_batch()

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Method clone()

The objects of this class are cloneable with this method.

Usage

RecordBatchReader$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Super classes

arrow::Object -> arrow::RecordBatchReader -> RecordBatchStreamReader

Methods

Public methods

• RecordBatchStreamReader$batches()

• RecordBatchStreamReader$clone()

Inherited methods

• arrow::Object$initialize()

• arrow::Object$pointer()

• arrow::Object$print()

• arrow::Object$set_pointer()

• arrow::RecordBatchReader$read_next_batch()

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Method batches()

Usage

RecordBatchStreamReader$batches()

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Method clone()

The objects of this class are cloneable with this method.

Usage

RecordBatchStreamReader$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Super class

arrow::Object -> RecordBatchFileReader

Methods

Public methods

• RecordBatchFileReader$get_batch()

• RecordBatchFileReader$batches()

• RecordBatchFileReader$clone()

Inherited methods

• arrow::Object$initialize()

• arrow::Object$pointer()

• arrow::Object$print()

• arrow::Object$set_pointer()

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Method get_batch()

Usage

RecordBatchFileReader$get_batch(i)

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Method batches()

Usage

RecordBatchFileReader$batches()

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Method clone()

The objects of this class are cloneable with this method.

Usage

RecordBatchFileReader$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.