Implement repository pattern in Go

Database Web Database
2026-04-17T12:05:42+00:00
Implement the repository pattern in Go by defining an interface for data operations and creating a struct that implements it to abstract database interactions.

Implement the repository pattern by defining an interface for your data operations and creating a struct that implements it to interact with your data source. This separates your business logic from data access details.

// Define the interface
type UserRepository interface {
    GetByID(id int) (*User, error)
    Save(user *User) error
}

// Implement the interface
type PostgresUserRepository struct {
    db *sql.DB
}

func (r *PostgresUserRepository) GetByID(id int) (*User, error) {
    var user User
    err := r.db.QueryRow("SELECT * FROM users WHERE id = $1", id).Scan(&user.ID, &user.Name)
    return &user, err
}

func (r *PostgresUserRepository) Save(user *User) error {
    _, err := r.db.Exec("INSERT INTO users (id, name) VALUES ($1, $2)", user.ID, user.Name)
    return err
}