Enum ViewMode 

#[non_exhaustive]
pub enum ViewMode {
    Virtual,
    Materialized {
        top_k: u32,
    },
}

View mode.

use kevy_index::{IndexValue, Leaf, Tree, ViewMode, ViewSpec};
let t = Tree::Leaf(Leaf::new("age", IndexValue::I64(0), IndexValue::I64(99)));
let v = ViewSpec::new("v", t, "age");
assert_eq!(v.mode, ViewMode::Virtual, "views are virtual unless declared otherwise");

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Virtual

Evaluate the tree at query time.

use kevy_index::ViewMode;
assert_eq!(ViewMode::Virtual.name(), "virtual");

Materialized

Maintain an incremental result set; top_k = 0 = unbounded.

use kevy_index::ViewMode;
let m = ViewMode::Materialized { top_k: 10 };
assert_eq!(m.name(), "materialized");

Fields

top_k: u32

Bounded size (0 = keep every member).

use kevy_index::{IndexValue, MaterializedSet, Membership, SortOrder};
// K = 2 keeps K + K/4 = 2 members
let mut top2 = MaterializedSet::new(2, SortOrder::Desc);
for (k, v) in [(b"a", 1), (b"b", 5), (b"c", 3)] {
    top2.apply(k, Membership::Member(Some(IndexValue::I64(v))));
}
assert_eq!(top2.len(), 2, "top_k bounds the members kept");
assert_eq!(top2.page(None, 9)[1], (IndexValue::I64(3), b"c".to_vec()));

Implementations

impl ViewMode

pub fn name(&self) -> &'static str

The mode as VIEW.CREATE … MODE and the describe replies spell it.

use kevy_index::ViewMode;
assert_eq!(ViewMode::Virtual.name(), "virtual");
assert_eq!(ViewMode::Materialized { top_k: 5 }.name(), "materialized");

Trait Implementations

impl Clone for ViewMode

fn clone(&self) -> ViewMode

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for ViewMode

impl Debug for ViewMode

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for ViewMode

impl Hash for ViewMode

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ViewMode

fn eq(&self, other: &ViewMode) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ViewMode