Relationships

Sea-ORM supports three types of relationships: BelongsTo, HasMany, and HasOne.

Defining Relationships

#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
pub enum Relation {
    // Belongs To (many-to-one)
    #[sea_orm(
        belongs_to = "super::sys_dept::Entity",
        from = "Column::DeptId",
        to = "super::sys_dept::Column::Id"
    )]
    Dept,

    // Has Many (one-to-many)
    #[sea_orm(
        has_many = "super::sys_login_log::Entity",
        from = "Column::Id",
        to = "super::sys_login_log::Column::UserId"
    )]
    LoginLogs,
}

Querying with Relations

use sea_orm::{EntityTrait, RelationTrait};

// Find user with their department
let user = entity::sys_user::Entity::find_by_id(1001)
    .find_also_related(entity::sys_dept::Entity)
    .one(&db).await?;
// Result: Option<(Model, Option<sys_dept::Model>)>