hp order-a-cartridge打印机驱动 GoFrame 数据查询-Group/Order/Having

Group/Order分组与排序

​Group​方法用于查询分组，​Order​方法用于查询排序。使用示例：

// SELECT COUNT(*) total,age FROM `user` GROUP BY age
g.Model("user").Fields("COUNT(*) total,age").Group("age").All()

// SELECT * FROM `student` ORDER BY class asc,course asc,score desc
g.Model("student").Order("class asc,course asc,score desc").All()

同时，​goframe​的​ORM​提供了一些常用的排序方法：

// 按照指定字段递增排序
func (m *Model) OrderAsc(column string) *Model
// 按照指定字段递减排序
func (m *Model) OrderDesc(column string) *Model
// 随机排序
func (m *Model) OrderRandom() *Model

使用示例：

// SELECT `id`,`title` FROM `article` ORDER BY `created_at` ASC
g.Model("article").Fields("id,title").OrderAsc("created_at").All()

// SELECT `id`,`title` FROM `article` ORDER BY `views` DESC
g.Model("article").Fields("id,title").OrderDesc("views").All()

// SELECT `id`,`title` FROM `article` ORDER BY RAND()
g.Model("article").Fields("id,title").OrderRandom().All()

Having条件过滤

​Having​方法用于查询结果的条件过滤。使用示例：

// SELECT COUNT(*) total,age FROM `user` GROUP BY age HAVING total>100
g.Model("user").Fields("COUNT(*) total,age").Group("age").Having("total>100").All()

// SELECT * FROM `student` ORDER BY class HAVING score>60
g.Model("student").Order("class").Having("score>?", 60).All()