gorm使用场景 - Githubissues

多对多情况

package main

import (
    "encoding/json"
    "fmt"
    "github.com/jinzhu/gorm"
    _ "github.com/jinzhu/gorm/dialects/sqlite"
    "testing"
)

type User struct {
    gorm.Model
    Name   string
    Groups []Group `gorm:"many2many:user_group;"`
}

type Group struct {
    gorm.Model
    Name  string
    Users []User `gorm:"many2many:user_group;"`
}

func TestMany2Many(t *testing.T) {
    db, err := gorm.Open("sqlite3", "test.db")
    db.LogMode(true)
    if err != nil {
        panic("failed to connect database")
    }

    db.AutoMigrate(&User{}, &Group{})

    createTestData(db)

    //获取某一个用户以及用户所在组
    findUser(db)

    //获取某些用户以及用户所在组
    findUsers(db)

    defer db.Close()
}

func findUsers(db *gorm.DB) {
    var users []User
    db.Preload("Groups").Find(&users)
    fmt.Println(toJson(users))
}

func findUser(db *gorm.DB) {
    user1 := User{}
    db.First(&user1, 1)
    db.Model(&user1).Related(&user1.Groups, "groups")
    fmt.Println(toJson(user1))
}

func toJson(data interface{}) string {
    bytes, _ := json.Marshal(data)
    return string(bytes)
}

func createTestData(db *gorm.DB) {
    //根据用户维度插入数据
    user1Groups := []Group{
        Group{Name: "分组1-1"},
        Group{Name: "分组1-2"},
    }
    user1 := User{Name: "shuwei1", Groups: user1Groups}
    db.Create(&user1)

    //根据组维度插入数据
    group2 := Group{Name: "分组2-1", Users: []User{
        User{Name: "张三2"},
        User{Name: "张三3"},
    }}

    db.Create(&group2)

}

1对多或者1对1

package one2many

import (
    "encoding/json"
    "fmt"
    "github.com/jinzhu/gorm"
    _ "github.com/jinzhu/gorm/dialects/sqlite"
    "testing"
    "time"
)

type Person struct {
    gorm.Model
    Name   string `gorm:"size:64;index:name_index"` //大小64，索引
    Age    int
    IdCard IdCard
    Emails []Email
}

func (p Person) String() string {
    bytes, _ := json.Marshal(p)
    return string(bytes)
}

type IdCard struct {
    gorm.Model
    Numbers  string
    PersonId uint
    Expiry   time.Time
}

type Email struct {
    gorm.Model
    Address  string `gorm:"type:varchar(100)"`
    PersonId uint
}

func TestOne(t *testing.T) {
    db, err := gorm.Open("sqlite3", "test.db")
    if err != nil {
        panic("failed to connect database")
    }
    db.LogMode(true)
    db.AutoMigrate(&Person{}, &IdCard{}, &Email{})

    createData(db)

    //查询某个用户的全部信息
    findPerson(db)

    //查询所有用户的全部信息
    findPersons(db)

    defer db.Close()
}

func findPersons(db *gorm.DB) {
    var people []Person
    db.Preload("Emails").Preload("IdCard").Find(&people)
    //两种方式都可以

    var perple1 []Person
    db.Set("gorm:auto_preload", true).Find(&perple1)
    fmt.Println(people)
    fmt.Println(perple1)
}

func findPerson(db *gorm.DB) {
    var p Person
    db.First(&p, 1)
    db.Model(&p).Related(&p.IdCard).Related(&p.Emails)
    fmt.Println(p)
}

func createData(db *gorm.DB) {
    p1 := Person{Name: "shuwei", Age: 18,
        IdCard: IdCard{Numbers: "111111111111", Expiry: time.Now()},
        Emails: []Email{{Address: "shuvigoss@gmail.com"}, {Address: "241883644@qq.com"}},
    }

    p2 := Person{Name: "zhangsan", Age: 18,
        IdCard: IdCard{Numbers: "22222222", Expiry: time.Now()},
        Emails: []Email{{Address: "zhangsan@example.com"}, {Address: "zhangsan@qq.com"}},
    }

    db.Create(&p1).Create(&p2)
}

shuvigoss / notes

gorm使用场景 #2