高階查詢

isnull：判斷某個欄位是否為null

func (this *OperatorsController) GetIsNull() {
	user := models.User{}
	var users []*models.User
	orm := orm.NewOrm()//建立orm
	qs := orm.QueryTable(user)//建立控制程式碼
	n, err := qs.Filter("name__isnull", false).All(&users)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("n = ", n)
	for _, u := range users {
		fmt.Println("u = ", u)
	}
	this.Ctx.WriteString("查詢成功!")
}

in：和sql中得in含義相同，通常和Filter結合使用

func (this *OperatorsController) GetIn() {
	user := models.User{}
	var users []*models.User
	//建立orm
	orm := orm.NewOrm()
	//建立控制程式碼
	qs := orm.QueryTable(user)
	//SELECT * FROM USER WHERE id IN(2, 5, 6);
	/*buffer := []int{ 13, 14, 15, 16}
	n, err := qs.Filter("id__in", buffer).All(&users)*/
	n, err := qs.Filter("id__in", 13, 14, 15, 16).All(&users)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("n = ", n)
	for _, u := range users {
		fmt.Println("u = ", u)
	}
	this.Ctx.WriteString("查詢成功!")
}

istartswith：判斷某個欄位是否以指定內容開始

func (this *OperatorsController) GetStartswith() {
	user := models.User{}
	var users []*models.User
	//建立orm
	orm := orm.NewOrm()
	//建立控制程式碼
	qs := orm.QueryTable(user)
	//SELECT * FROM USER WHERE NAME LIKE '杜%'
	n, err := qs.Filter("name__startswith", "B").All(&users)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("n = ", n)
	for _, u := range users {
		fmt.Println("u = ", u)
	}
	this.Ctx.WriteString("查詢成功!")
}

gt：大於，通常和Filter結合使用

func (this *OperatorsController) GetGt() {
	user := models.User{}
	var users []*models.User
	//建立orm
	orm := orm.NewOrm()
	//建立控制程式碼
	qs := orm.QueryTable(user)
	//SELECT * FROM USER WHERE id > 2;
	n, err := qs.Filter("id__gt", 14).All(&users)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("n = ", n)
	for _, u := range users {
		fmt.Println("u = ", u)
	}
	this.Ctx.WriteString("查詢成功!")
}

contains：判斷某個欄位是否 包含指定欄位

func (this *OperatorsController) GetContains() {
	user := models.User{}
	//建立使用者指標切片，用於儲存查詢結果
	var users []*models.User
	//建立orm
	orm := orm.NewOrm()
	//建立控制程式碼
	qs := orm.QueryTable(user)
	//SELECT * FROM USER WHERE NAME LIKE '%紫%';
	n, err := qs.Filter("name__contains", "o").All(&users)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("n = ", n)
	for _, u := range users {
		fmt.Println("u = ", u)
	}
	this.Ctx.WriteString("查詢成功!")
}

exact：對某個條件取反

func (this *OperatorsController) GetExact() {
	user := models.User{}
	//建立orm
	orm := orm.NewOrm()
	//建立控制程式碼
	qs := orm.QueryTable("user")
	//SELECT * FROM USER WHERE id = 7;
	//在user表中查詢id等於12的使用者
	err := qs.Filter("id__exact", 12).One(&user)
	if err != nil {
		this.Ctx.WriteString("查詢失敗!")
		return
	}
	fmt.Println("user = ", user)
	this.Ctx.WriteString("查詢成功!")
}

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