Skip to main contentModule select_projection
Source - select_first
.select(...).first() lifts the outer container to Option<T>.- select_first_no_match
.select(...).first() returns None when no rows match.- select_single_field
.select(field) on a Query<List<Item>> returns a Query<List<String>>
whose .exec() produces a Vec<String> of the projected column.- select_tuple
.select((f1, f2)) returns a Query<List<(T1, T2)>> whose .exec()
produces a Vec of tuples.- select_with_filter
.select(...) composes with .filter(...): the projection sees only rows
matching the filter expression.