go_orm

初学GO 自己封装的orm 旨在技术学习

目录

1. ORM
2. Model约定
3. 如何使用
4. 链接数据库
5. CURD使用方法
6. 事务
7. GQL
8. NULL
9. map
10. 分页
11. 命名规则（驼峰转为下划线）

ORM

使用反射

Model约定

1. tag sql 代表数据库中的字段 不注明 则使用结构体字段
2. 数据库表 不区分大小写

type Student struct {
	Id int `sql:"id"` 
	Name string `sql:"name"`
	Address string `sql:"address"`
	No string
	ClassId int `sql:"class_id"`
}

引入包

import "github.com/zhuzhiqiang18/go_orm"

链接数据库

只支持MYSQL

 db, err := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
   	defer db.Close()

CURD使用方法

插入

  db, err := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
  	defer db.Close()
  	if err!=nil {
  		fmt.Println(err)
  		return
  	}
  	var student model.Student
  	student.Name="张三"
  	student.Address="中国"
  	student.No="123456"
  	student.ClassId=1
  	student.Create = time.Now()
  	student.IsReading =true
  	res, lastInsertId := db.Save(&student)
  	fmt.Println("改变行数",res)
  	fmt.Println("最后插入的id",lastInsertId)

删除

  db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
  	defer db.Close()
  	var student model.Student
  	student.ClassId=1
  	res:= db.Delete(&student,"class_id")
  	fmt.Println("改变行数",res)

更改

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	var student model.Student
	student.Name="张三"
	student.No="00000000"
	res:= db.Update(&student,"name")
	fmt.Println("改变行数",res)

查询

单表全查询

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	//传类型地址
	list := make([]model.Student,0)
	err := db.FindQuery(&list, "select * from student ")
	if err!=nil {
		fmt.Println(err)
	}else {
		for _,stu := range list {
			fmt.Println(stu)
		}

	}

单表指定字段查询

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	//传类型地址
	list := make([]model.Student,0)
	err := db.FindQuery(&list, "select name,no from student ")
	if err!=nil {
		fmt.Println(err)
	}else {
		for _,stu := range list {
			fmt.Println(stu)
		}

	}

条件查询

条件查询使用tag sql字段

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	//传类型地址
	list := make([]model.Student,0)
	err := db.FindQuery(&list, "select name,no from student where name=? ","张三")
	if err!=nil {
		fmt.Println(err)
	}else {
		for _,stu := range list {
			fmt.Println(stu)
		}

	}

联合查询

待更新……

事务

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	var student model.Student
	student.Name="张三"
	student.No="00000000"
    tx:=db.Begin()//获取事务
	for i:=0;i<10;i++{
		re, lastInsertId := tx.Save(&student)
		fmt.Println("改变条数",re)
		fmt.Println("最后插入主键",lastInsertId)
	}
	defer func() {
		err:=recover()
		if err !=nil {
			tx.Rollback()//事务回滚
			return
		}
	}()

	panic("事务回滚")

	tx.Commit()//事务提交

GQL

gql 是一个 sql 生成器

    //select * from Student where name ="张三" and class_id = 1
	var gql go_orm.Gql
	gql.Where("name = ? ").Where("class_id = ?").Bind(&model.Student{}).SetPara("张三",1)

   //select name,class_id from Student where name ="张三" and class_id = 1
   	new(go_orm.Gql).Where("name = ? ").Where("class_id = ?").Bind(&model.Student{}).SetPara("张三",1).Fields("name","class_id")
   
   	//select name,class_id from Student where name ="张三" and class_id = 1 or class_id = 2
   	new(go_orm.Gql).Where("name = ? ").Where("class_id = ?").Or("class_id = ?").Bind(&model.Student{}).SetPara("张三",1,2).Fields("name","class_id")
   
   	//select name,class_id from Student where name ="张三" and class_id = 1 or class_id = 2 order by id desc
   	new(go_orm.Gql).Where("name = ? ").Where("class_id = ?").Or("class_id = ?").Order("id desc").Bind(&model.Student{}).SetPara("张三",1,2).Fields("name","class_id")
   

gql查询

	var gql go_orm.Gql
    	students := make([]model.Student,0)
    	//select * from Student where name ="张三" and class_id = 1
    	gql.Where("name = ? ").Where("class_id = ?").Bind(&students).SetPara("张三",1)
    
    	db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
    	defer db.Close()
    	err := db.FindGql(&gql)
    
    	if err!=nil {
    		fmt.Println(err)
    		return
    	}
    
    	for _,stu := range students {
    		fmt.Println(stu)
    	}

NULL

GO中没有NULL 为适配数据库中的NULL 以及JSON的NULL 引入第三方包 gopkg.in/guregu/null.v3 方便数据适配

示例

type Teacher struct {
	Id null.Int `sql:"id"`
	Name null.String `sql:"name"`
	Address null.String `sql:"address"`
	No null.String `sql:"no"`
	ClassId null.Int `sql:"class_id"`
	Create null.Time `sql:"create_date"`
	IsReading null.Bool `sql:"is_reading"`
	High null.Float `sql:"high"`
	Weight null.Float `sql:"weight"`
}



var teacher model.Teacher
	teacher.Name = null.NewString("zzq",true)
	teacher.Create = null.NewTime(time.Now(),true)
	teacher.IsReading = null.NewBool(true,true)
	teacher.High = null.NewFloat(160.256,true)
	db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	defer db.Close()
	count,last:= db.Save(&teacher);
	fmt.Println("改变条数" , count)
	fmt.Println("最后插入" , last)


var gql go_orm.Gql
	teachers := make([]model.Teacher,0)
	//select * from Student where name ="zzq" and class_id = 1
	gql.Where("name = ? ").Where("is_reading = ?").Bind(&teachers).SetPara("zzq",1)

	db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	db.DBSetting().SetFieldFormat(go_orm.HUMP_UNDERLINE)//驼峰下划线
	db.DBSetting().SetTableFormat(go_orm.HUMP_UNDERLINE)//驼峰下划线
	defer db.Close()
	err := db.FindGql(&gql)
	if err != nil{
		panic(err)
	}

	for _,th := range teachers {
		fmt.Println(th)
		jsonStr,_:=json.Marshal(th)
		fmt.Println(string(jsonStr))
//{"Id":1,"Name":"zzq","Address":null,"No":null,"ClassId":null,"Create":"2019-08-20T14:48:12Z","IsReading":true,"High":null,"Weight":null}

命名规则

db, _ := go_orm.Open("root","123456","127.0.0.1",3306,"go_test")
	db.DBSetting().SetFieldFormat(go_orm.HUMP_UNDERLINE)//字段驼峰转下划线
	db.DBSetting().SetTableFormat(go_orm.HUMP_UNDERLINE)//表名驼峰转下划线

字段设置驼峰转下划线 如字段tag为空则转下划线方式 如设置tag 则使用tag