Skip to main content
Version: 0.4.x

Entity Structure

Let's look at a simple Cake entity.

use sea_orm::entity::prelude::*;

#[derive(Clone, Debug, PartialEq, DeriveEntityModel)]
#[sea_orm(table_name = "cake")]
pub struct Model {
pub id: i32,
pub name: String,

#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
pub enum Relation {
#[sea_orm(has_many = "super::fruit::Entity")]

impl ActiveModelBehavior for ActiveModel {}


The DeriveEntityModel macro does all the heavy lifting of defining an Entity with associating Model, Column and PrimaryKey.

Table Name

The table_name attribute specifies the corresponding table in the database. Optionally, you can also specify the database schema by schema_name (Postgres only).

#[sea_orm(table_name = "cake", schema_name = "public")]
pub struct Model { ... }


Column Type

The column type will be derived automatically with the following mapping:

Rust typeDatabase Type
u8, i8TinyInteger
u16, i16SmallInteger
u32, i32Integer
u64, i64BigInteger
DateTime (chrono::NaiveDateTime)DateTime
DateTimeWithTimeZone (chrono::DateTime<FixedOffset>)TimestampWithTimeZone
Uuid (uuid::Uuid)Uuid
Json (serde_json::Value)Json
Decimal (rust_decimal::Decimal)Decimal

You can override the default mappings between a Rust type and ColumnType by the column_type attribute.

#[sea_orm(column_type = "Text")]
pub name: String

Additional Properties

You can add additional properties unique, indexed and nullable to a column.

If you specified a custom column_type for an optional attribute, you must also specify nullable.

#[sea_orm(column_type = "Text", unique, indexed, nullable)]
pub name: Option<String>

Ignore Attribute

If you want to ignore a particular model attribute such that it maps to no database column, you can use the ignore annotation.

pub ignore_me: String

Primary Key

Use the primary_key attribute to mark a column as the primary key.

pub id: i32

Auto Increment

By default, auto_increment is implied. Override by specifying false.

#[sea_orm(primary_key, auto_increment = false)]
pub id: i32

Composite Key

This is usually the case in junction tables, where a two-column tuple is used as the primary key. Simply annotate multiple columns to define a composite primary key.

pub struct Model {
pub cake_id: i32,
pub fruit_id: i32,


The DeriveRelation macro is a simple wrapper to impl the RelationTrait.

pub enum Relation {
#[sea_orm(has_many = "super::fruit::Entity")]

expands into

impl RelationTrait for Relation {
fn def(&self) -> RelationDef {
match self {
Self::Fruit => Entity::has_many(super::fruit::Entity).into(),

Learn more about relations in the next section.