sea_orm/query/
traits.rs

1use crate::{DbBackend, Statement, StatementBuilder};
2
3/// A Trait for any type performing queries on a Model or ActiveModel
4pub trait QueryTrait {
5    /// Constrain the QueryStatement to [StatementBuilder] trait
6    type QueryStatement: StatementBuilder;
7
8    /// Get a mutable ref to the query builder
9    fn query(&mut self) -> &mut Self::QueryStatement;
10
11    /// Get an immutable ref to the query builder
12    fn as_query(&self) -> &Self::QueryStatement;
13
14    /// Take ownership of the query builder
15    fn into_query(self) -> Self::QueryStatement;
16
17    /// Build the query as [`Statement`]
18    fn build(&self, db_backend: DbBackend) -> Statement {
19        StatementBuilder::build(self.as_query(), &db_backend)
20    }
21
22    /// Apply an operation on the [QueryTrait::QueryStatement] if the given `Option<T>` is `Some(_)`
23    ///
24    /// # Example
25    ///
26    /// ```
27    /// use sea_orm::{DbBackend, entity::*, query::*, tests_cfg::cake};
28    ///
29    /// assert_eq!(
30    ///     cake::Entity::find()
31    ///         .apply_if(Some(3), |mut query, v| {
32    ///             query.filter(cake::Column::Id.eq(v))
33    ///         })
34    ///         .apply_if(Some(100), QuerySelect::limit)
35    ///         .apply_if(None, QuerySelect::offset::<Option<u64>>) // no-op
36    ///         .build(DbBackend::Postgres)
37    ///         .to_string(),
38    ///     r#"SELECT "cake"."id", "cake"."name" FROM "cake" WHERE "cake"."id" = 3 LIMIT 100"#
39    /// );
40    /// ```
41    fn apply_if<T, F>(self, val: Option<T>, if_some: F) -> Self
42    where
43        Self: Sized,
44        F: FnOnce(Self, T) -> Self,
45    {
46        if let Some(val) = val {
47            if_some(self, val)
48        } else {
49            self
50        }
51    }
52}
sea_orm/query/traits.rs

sea_orm/query/
traits.rs
