golang Gorm 运用及执行原生SQL

package dbhelper

import (
    "github.com/jinzhu/gorm"
    _ "github.com/jinzhu/gorm/dialects/mysql"
)

/// 连接数据库得到
func GetConn() (*gorm.DB,error) {
    db,err :=gorm.Open("mysql","root:123456@(192.168.0.100:3306)/mytest?charset=utf8mb4&parseTime=True&loc=Local")
    return db,err
}

type User struct {
    Uid uint `gorm:"column:uid;primary_key;AUTO_INCREMENT"`
    UserName string
    Age uint
    Bj string
}

package createtable

import (
    "GinMysql/dbhelper"
    "GinMysql/model"
    _ "github.com/jinzhu/gorm/dialects/mysql"
    "log"
)

func init(){
    var user model.User
    var userinfo model.UserInfo
    db,err := dbhelper.GetConn()
    if err!=nil{
        log.Panicln("连接数据库出错：",err)
    }

     db.SingularTable(true)   // 不设置表名为复数

// 数据迁移 到Mysql
    db.AutoMigrate(&user)
    db.AutoMigrate(&userinfo)

}

package main

import (
    // 引用 createtable 调用init方法
    _ "GinMysql/createtable"
    "GinMysql/route"
)


func main(){
    engin:= route.SetUpRoute()
    engin.Run(":8090")
}

type Mycount struct {
    Usercount uint
}

    //  关于Gorm执行原生SQL
    // **********语句字段要小写************
    // ***********查询用db.Raw,其他用db.Exec
    // *********** 字段大小写要对应上 **************
    // *************** 注意要 defer rows.Close()
    var Mycount Mycount
    rows,_:= db.Debug().Raw("select Count(1) as Usercount from Users").Rows()
    defer rows.Close()
    for rows.Next() {
        rows.Scan(&Mycount.Usercount)
    }
    var users []User
    //   查询 执行用Scan 和Find 一样
    db=db.Raw("select uid,user_name,age from Users").Scan(&users)
    //db=db.Raw("select uid,user_name,age from Users").Find(&users)
    fmt.Println("Users",users)
    //  更新和删除.插入用 Exec
    db= db.Exec("update Users set user_name='def' where uid=?",1)
    fmt.Println("更新了",db.RowsAffected,"条数据")
    db= db.Exec("delete from Users where uid=?",2)
    fmt.Println("更新了",db.RowsAffected,"条数据")
    return  int32(Mycount.Usercount)

 

 

    var mycont int
    // count 使用
    db.Debug().Model(&Myaaa{}).Where("id<?",10).Count(&mycont)
    // 更新
    db.Debug().Model(&Myaaa{}).Update(my)
    // 分页   Offset 跳过     Order 排序
    db.Limit(2).Offset(1).Order("id desc").Where("id>?",0).Find(&bbb)
    // 删除
    db.Delete(my)