Function project_schema

datafusion/common/src/utils/mod.rs:82–91

Applies an optional projection to a [`SchemaRef`], returning the projected schema Example: ``` use arrow::datatypes::{DataType, Field, Schema, SchemaRef}; use datafusion_common::project_schema; // Schema with columns 'a', 'b', and 'c' let schema = SchemaRef::new(Schema::new(vec![ Field::new("a", DataType::Int32, true), Field::new("b", DataType::Int64, true), Field::new("c", DataType::Utf8, true)

(
    schema: &SchemaRef,
    projection: Option<&impl AsRef<[usize]>>,
)

/// assert_eq!(projected_schema, expected_schema);
/// ```
pub fn project_schema(
    schema: &SchemaRef,
    projection: Option<&impl AsRef<[usize]>>,
) -> Result<SchemaRef> {
    let schema = match projection {
        Some(columns) => Arc::new(schema.project(columns.as_ref())?),
        None => Arc::clone(schema),
    };
    Ok(schema)
}

/// Extracts a row at the specified index from a set of columns and stores it in the provided buffer.
pub fn extract_row_at_idx_to_buf(