Trait Selectable

Source

pub trait Selectable<T, C = Expression<T>>:
    Send
    + Sync
    + Debug
    + Clone {
Show 33 methods    // Required methods
    fn add_source(
        &mut self,
        source: impl Into<SourceRef<T>>,
        alias: Option<String>,
    );
    fn add_field(&mut self, field: impl Into<String>);
    fn add_expression(&mut self, expression: impl Expressive<T>);
    fn add_where_condition(&mut self, condition: impl Into<C>);
    fn set_distinct(&mut self, distinct: bool);
    fn add_order_by(&mut self, order: impl Into<C>, direction: Order);
    fn add_group_by(&mut self, expression: impl Expressive<T>);
    fn set_limit(&mut self, limit: Option<i64>, skip: Option<i64>);
    fn clear_fields(&mut self);
    fn clear_where_conditions(&mut self);
    fn clear_order_by(&mut self);
    fn clear_group_by(&mut self);
    fn has_fields(&self) -> bool;
    fn has_where_conditions(&self) -> bool;
    fn has_order_by(&self) -> bool;
    fn has_group_by(&self) -> bool;
    fn is_distinct(&self) -> bool;
    fn get_limit(&self) -> Option<i64>;
    fn get_skip(&self) -> Option<i64>;
    fn as_field(&self, field: impl Into<String>) -> Expression<T>;
    fn as_count(&self) -> Expression<T>;
    fn as_sum(&self, column: impl Expressive<T>) -> Expression<T>;
    fn as_max(&self, column: impl Expressive<T>) -> Expression<T>;
    fn as_min(&self, column: impl Expressive<T>) -> Expression<T>;

    // Provided methods
    fn with_source(self, source: impl Into<SourceRef<T>>) -> Self
       where Self: Sized { ... }
    fn with_source_as(
        self,
        source: impl Into<SourceRef<T>>,
        alias: impl Into<String>,
    ) -> Self
       where Self: Sized { ... }
    fn with_condition(self, condition: impl Into<C>) -> Self
       where Self: Sized { ... }
    fn with_order(self, order: impl Into<C>, direction: Order) -> Self
       where Self: Sized { ... }
    fn with_field(self, field: impl Into<String>) -> Self
       where Self: Sized { ... }
    fn with_expression(self, expression: impl Expressive<T>) -> Self
       where Self: Sized { ... }
    fn with_group_by(self, expression: impl Expressive<T>) -> Self
       where Self: Sized { ... }
    fn with_distinct(self, distinct: bool) -> Self
       where Self: Sized { ... }
    fn with_limit(self, limit: Option<i64>, skip: Option<i64>) -> Self
       where Self: Sized { ... }
}

Expand description

Unified protocol for building SELECT queries across different databases.

The Selectable trait provides a standardized interface for building SELECT-style queries that work with databases supporting columns, conditions, ordering, limits, and aggregations. This allows the same query building patterns to work across SQL databases, SurrealDB, MongoDB, and other backends.

The trait is parameterized on:

T — the value/expression type (e.g. AnySqliteType, AnyMongoType)
C — the condition type, defaults to Expression<T> for SQL backends. Document-oriented backends like MongoDB can use bson::Document or a custom condition type.

Implementations handle database-specific syntax while exposing a consistent API for field selection, filtering, sorting, grouping, and aggregation operations. The trait supports both mutable builder methods and fluent chainable methods.