Struct MapVariantToArrowRowBuilder 

pub(crate) struct MapVariantToArrowRowBuilder<'a> {
    entries_field: &'a FieldRef,
    key_field: &'a FieldRef,
    value_field: &'a FieldRef,
    ordered: bool,
    key_builder: Box<VariantToArrowRowBuilder<'a>>,
    value_builder: Box<VariantToArrowRowBuilder<'a>>,
    offsets: Vec<i32>,
    current_offset: i32,
    nulls: NullBufferBuilder,
    cast_options: &'a CastOptions<'a>,
}

Builder for converting variant objects into Arrow MapArrays.

Each variant object field becomes one map entry: the field name is the map key and the field value is converted to the requested value type. Variant objects store their fields in lexicographic key order, so maps with string keys come out sorted by key.

Fields

entries_field: &'a FieldRef

key_field: &'a FieldRef

value_field: &'a FieldRef

ordered: bool

key_builder: Box<VariantToArrowRowBuilder<'a>>

value_builder: Box<VariantToArrowRowBuilder<'a>>

offsets: Vec<i32>

current_offset: i32

nulls: NullBufferBuilder

cast_options: &'a CastOptions<'a>

Implementations

impl<'a> MapVariantToArrowRowBuilder<'a>

fn try_new( entries_field: &'a FieldRef, ordered: bool, cast_options: &'a CastOptions<'_>, capacity: usize, ) -> Result<Self>

fn append_null(&mut self) -> Result<()>

fn append_value(&mut self, value: &Variant<'_, '_>) -> Result<bool>

fn finish(self) -> Result<ArrayRef>