Struct mz_arrow_util::builder::ArrowBuilder

pub struct ArrowBuilder {
    columns: Vec<ArrowColumn>,
    row_size_bytes: usize,
}

Fields

columns: Vec<ArrowColumn>

row_size_bytes: usize

A crude estimate of the size of the data in the builder based on the size of the rows added to it.

Implementations

impl ArrowBuilder

pub fn validate_desc(desc: &RelationDesc) -> Result<(), Error>

Helper to validate that a RelationDesc can be encoded into Arrow.

pub fn new( desc: &RelationDesc, item_capacity: usize, data_capacity: usize, ) -> Result<Self, Error>

Initializes a new ArrowBuilder with the schema of the provided RelationDesc. item_capacity is used to initialize the capacity of each column’s builder which defines the number of values that can be appended to each column before reallocating. data_capacity is used to initialize the buffer size of the string and binary builders. Errors if the relation contains an unimplemented type.

pub fn schema(&self) -> Schema

Returns a copy of the schema of the ArrowBuilder.

pub fn to_record_batch(self) -> Result<RecordBatch, ArrowError>

Converts the ArrowBuilder into an arrow RecordBatch.

pub fn add_row(&mut self, row: &Row) -> Result<(), Error>

Appends a row to the builder. Errors if the row contains an unimplemented or out-of-range value.

pub fn row_size_bytes(&self) -> usize