Test of Gorm's Foreign Key Functionality

ForeignKeyTest.go

package main

import (
	"database/sql"
	"fmt"
	"time"

	"github.com/jinzhu/gorm"
	_ "github.com/mattn/go-sqlite3"
)

type User struct {
	Id        int64
	Birthday  time.Time
	Age       int64
	Name      string `sql:"size:255"`
	CreatedAt time.Time
	UpdatedAt time.Time
	DeletedAt time.Time

	Emails            []Email       // Embedded structs
	BillingAddress    Address       // Embedded struct
	BillingAddressId  sql.NullInt64 // BillingAddress's foreign key
	ShippingAddress   Address       // Another Embedded struct with same type
	ShippingAddressId int64         // ShippingAddress's foreign key
	IgnoreMe          int64         `sql:"-"` // Ignore this field
}

type Address struct {
	Id       int64
	Address1 string         `sql:"not null;unique"` // Set this field as not nullable and unique in database
	Address2 string         `sql:"type:varchar(100);unique"`
	Post     sql.NullString `sql:not null`
	// FYI, "NOT NULL" will only work well with NullXXX Scanner, because golang will initalize a default value for most type...
}

type Email struct {
	Id         int64
	UserId     int64  // Foreign key for User
	Email      string `sql:"type:varchar(100);"` // Set this field's type
	Subscribed bool
}

func main() {
	db, err := gorm.Open("sqlite3", "test.db")
	if err != nil {
		panic(fmt.Sprintf("Got error when connect database, the error is '%v'", err))
	}
	user := User{
		Name:            "jinzhu",
		BillingAddress:  Address{Address1: "Billing Address - Address 1"},
		ShippingAddress: Address{Address1: "Shipping Address - Address 1"},
		Emails:          []Email{{Email: "jinzhu@example.com"}, {Email: "jinzhu-2@example@example.com"}},
	}
	db.CreateTable(User{})
	db.CreateTable(Email{})
	db.CreateTable(Address{})
	err = db.Debug().Save(user).Error
	if err != nil {
		fmt.Println(err)
	}
}

/* Output
main.go:59 [2014-04-28 11:56:03] INSERT INTO addresses ("address1","address2","post") VALUES ('Billing Address - Address 1','','{ false}')

main.go:59) column address2 is not unique

main.go:59)[2014-04-28 11:56:03] INSERT INTO addresses ("address1","address2","post") VALUES ('Shipping Address - Address 1','','{ false}')

main.go:59)[2014-04-28 11:56:03] INSERT INTO users ("birthday","age","name","created_at","updated_at","deleted_at","billing_address_id","shipping_address_id") VALUES ('0001-01-01 0
0:00:00 +0000 UTC','0','jinzhu','0001-01-01 00:00:00 +0000 UTC','0001-01-01 00:00:00 +0000 UTC','0001-01-01 00:00:00 +0000 UTC','{0 false}','0')

main.go:59)[2014-04-28 11:56:03] INSERT INTO emails ("user_id","email","subscribed") VALUES ('0','jinzhu@example.com','false')

main.go:59)[2014-04-28 11:56:03] INSERT INTO emails ("user_id","email","subscribed") VALUES ('0','jinzhu-2@example@example.com','false')
*/