Introduction

Quick Summary#

Schema describes the definition of one entity type in the graph, like User or Group, and can contain the following configurations:

Entity fields (or properties), like: name or age of a User.
Entity edges (or relations), like: User's groups, or User's friends.
Database specific options, like: indexes or unique indexes.

Here's an example of a schema:

package schema

import (
    "entgo.io/ent"
    "entgo.io/ent/schema/field"
    "entgo.io/ent/schema/edge"
    "entgo.io/ent/schema/index"
)

type User struct {
    ent.Schema
}

func (User) Fields() []ent.Field {
    return []ent.Field{
        field.Int("age"),
        field.String("name"),
        field.String("nickname").
            Unique(),
    }
}

func (User) Edges() []ent.Edge {
    return []ent.Edge{
        edge.To("groups", Group.Type),
        edge.To("friends", User.Type),
    }
}

func (User) Index() []ent.Index {
    return []ent.Index{
        index.Fields("age", "name").
            Unique(),
    }
}

Entity schemas are usually stored inside ent/schema directory under the root directory of your project, and can be generated by entc as follows:

go run entgo.io/ent/cmd/ent init User Group

It's Just Another ORM#

If you are used to the definition of relations over edges, that's fine. The modeling is the same. You can model with ent whatever you can model with other traditional ORMs. There are many examples in this website that can help you get started in the Edges section.