Type Definition arrow_array::builder::BinaryRunBuilder

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pub type BinaryRunBuilder<K> = GenericByteRunBuilder<K, BinaryType>;
Expand description

Array builder for RunArray that encodes binary values(BinaryType).

// Create a run-end encoded array with run-end indexes data type as `i16`.
// The encoded data is binary values.


let mut builder = BinaryRunBuilder::<Int16Type>::new();

// The builder builds the dictionary value by value
builder.append_value(b"abc");
builder.append_null();
builder.extend([Some(b"def"), Some(b"def"), Some(b"abc")]);
let array = builder.finish();

assert_eq!(
  array.run_ends(),
  &Int16Array::from(vec![Some(1), Some(2), Some(4), Some(5)])
);

// Values are polymorphic and so require a downcast.
let av = array.values();
let ava: &BinaryArray = as_generic_binary_array::<i32>(av.as_ref());

assert_eq!(ava.value(0), b"abc");
assert!(av.is_null(1));
assert_eq!(ava.value(2), b"def");
assert_eq!(ava.value(3), b"abc");