Struct VistaQuery 

#[non_exhaustive]
pub struct VistaQuery {
    pub conditions: Vec<Condition>,
    pub search: Option<String>,
    pub order: Option<(String, SortDirection)>,
    pub native: Vec<String>,
}

Every clause applied through a Vista: its conditions, search and order, plus the keys of its driver-native conditions (NativeCondition::key). A native condition itself is opaque, so only its key is recorded, and a VistaQuery that holds native keys can’t be re-applied to another Vista.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

conditions: Vec<Condition>

search: Option<String>

order: Option<(String, SortDirection)>

native: Vec<String>

Implementations

impl VistaQuery

pub fn matches( &self, row: &Record<Value>, metadata: &VistaMetadata, ) -> Result<bool>

Whether row satisfies every condition and the search. The order doesn’t narrow, so it is ignored.

A native condition is opaque and can’t be evaluated in memory: a query holding any is an IncorrectUsage error. Check is_locally_evaluable first.

pub fn sort_rows( &self, rows: &mut [(String, Record<Value>)], metadata: &VistaMetadata, )

Sort rows by this query’s order; without one, rows keep theirs. A cell is read by cell_get, as matches reads it. An absent or null cell sorts last in both directions, and ties break on id, so the same rows always come back in the same order.

pub fn cmp_rows( &self, (a_id, a): (&str, &Record<Value>), (b_id, b): (&str, &Record<Value>), metadata: &VistaMetadata, ) -> Ordering

The order sort_rows sorts by: the order column, absent and null cells last in either direction, then ascending id. Without an order only the id decides, so Equal means the same id. Placing one row by a binary search over rows sort_rows sorted puts it where a fresh sort would.

pub fn is_locally_evaluable(&self) -> bool

Whether matches can evaluate this query: it holds no native conditions.

impl VistaQuery

pub fn new() -> Self

pub fn with_condition(self, condition: Condition) -> Self

pub fn with_search(self, text: impl Into<String>) -> Self

pub fn with_order(self, column: impl Into<String>, dir: SortDirection) -> Self

pub fn is_empty(&self) -> bool

No clause of any kind, order included.

pub fn key(&self) -> String

A stable string identifying this query, for cache identity. The same clauses give the same key whatever order the conditions (or native conditions) were added in, and different clauses give different keys: every part is length-prefixed and every value type-tagged, so no column name, text or value can be mistaken for a separator. Combine it with the Vista’s name to key a cache across tables.

Trait Implementations

impl Clone for VistaQuery

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for VistaQuery

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

Formats the value using the given formatter.

impl Default for VistaQuery

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for VistaQuery

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for VistaQuery