Trait SchemaLike

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pub trait SchemaLike {
    type Row;
    type Builders: BuildersLike<Row = Self::Row>;

    // Required methods
    fn schema_ref(&self) -> Arc<Schema>;
    fn new_builders(&self, capacity: usize) -> Self::Builders;

    // Provided method
    fn build_batch<I>(
        &self,
        rows: I,
    ) -> Result<RecordBatch, <Self::Builders as BuildersLike>::Error>
       where I: IntoIterator<Item = Self::Row> { ... }
}

Expand description

Unified schema abstraction: exposes Arrow schema and row/builder types.

Required Associated Types§

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type Row

The row type produced/consumed for this schema.

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type Builders: BuildersLike<Row = Self::Row>

Concrete builders used to accumulate rows into columns.

Required Methods§

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fn schema_ref(&self) -> Arc<Schema>

Return a shared reference to the underlying Arrow Schema.

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fn new_builders(&self, capacity: usize) -> Self::Builders

Create new column builders with a given capacity hint.

Provided Methods§

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fn build_batch<I>( &self, rows: I, ) -> Result<RecordBatch, <Self::Builders as BuildersLike>::Error>
where I: IntoIterator<Item = Self::Row>,

Build a RecordBatch from an iterator of rows.

Capacity is inferred from the iterator’s size hint (upper bound if present, otherwise the lower bound). For ExactSizeIterators like Vec and slices this yields exact preallocation.