dongxing7318 2017-07-05 14:11
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如何使用ozzo-dbx软件包在PostgreSQL中加入联接?

I am creating REST API in Go. And I want on request send the response with data about the object + some subdata about it which is another table. So basically do JOIN between tables.

I am using this package: https://github.com/go-ozzo/ozzo-dbx.

In the documentation, I failed to find JOIN examples.

Could you help me to solve this?

My code:

This does simple SELECT * FROM cars

func (dao *BikesDAO) Query(rs app.RequestScope, offset, limit int) ([]models.Bikes, error) {
bikes := []models.Bikes{}
err := rs.Tx().Select().OrderBy("name").Offset(int64(offset)).Limit(int64(limit)).All(&bikes)
return bikes, err
}

My structs:

type Bikes struct {
  Id                     int     `json:"id" db:"id"`
  Name                   string  `json:"name" db:"name"`
  Rating                 float64 `json:"rating" db:"rating"`
  PriceValue             uint    `json:"price_value" db:"price_value"`
  Users                  Users
}

type Users struct {
  Id             string  `json:"id" db:"id"`
  Username       string  `json:"username" db:"username"`
  Name           string  `json:"name" db:"name"`
  Phone          string  `json:"phone" db:"phone"`
  Email          string  `json:"email" db:"email"`
}

With this I want to do SELECT * FROM cars INNER JOIN users ON cars.user_id = users.id and get the following result:

{
 "id":12, 
 "name":"Toyota",
 "rating":4,
 "price_value":4000,
 "users": {
            "id":64,
            "Username":"Tom32",
            "Name":"Tom",
            "Phone":"325345345",
            "Email":"tom@gmail.com"
           }
 }
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1条回答 默认 最新

  • duanlv5084 2017-07-28 14:42
    关注

    After some digging in dbx package code I have found that it's quite easy:

    err := rs.Tx().Select().InnerJoin("table2", dbx.NewExp("table2.id = table1.id").OrderBy("name").Offset(int64(offset)).Limit(int64(limit)).All(&bikes)
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

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