Golang ORM with focus on PostgreSQL features and performance
url.Valuesinto structs.
NULL.
pg:",notnull"is used to add SQL
NOT NULLconstraint and
pg:",use_zero"to allow Go zero values.
LISTENand
NOTIFY.
COPY FROMand
COPY TO.
EXPLAINto get estimated number of matching rows.
go-pg supports 2 last Go versions and requires a Go version with modules support. So make sure to initialize a Go module:
go mod init github.com/my/repo
And then install go-pg (note v10 in the import; omitting it is a popular mistake):
go get github.com/go-pg/pg/v10
package pg_testimport ( "fmt"
"github.com/go-pg/pg/v10" "github.com/go-pg/pg/v10/orm"
)
type User struct { Id int64 Name string Emails []string }
func (u User) String() string { return fmt.Sprintf("User", u.Id, u.Name, u.Emails) }
type Story struct { Id int64 Title string AuthorId int64 Author *User
pg:"rel:has-one"
}func (s Story) String() string { return fmt.Sprintf("Story", s.Id, s.Title, s.Author) }
func ExampleDB_Model() { db := pg.Connect(&pg.Options{ User: "postgres", }) defer db.Close()
err := createSchema(db) if err != nil { panic(err) } user1 := &User{ Name: "admin", Emails: []string{"[email protected]", "[email protected]"}, } _, err = db.Model(user1).Insert() if err != nil { panic(err) } _, err = db.Model(&User{ Name: "root", Emails: []string{"[email protected]", "[email protected]"}, }).Insert() if err != nil { panic(err) } story1 := &Story{ Title: "Cool story", AuthorId: user1.Id, } _, err = db.Model(story1).Insert() if err != nil { panic(err) } // Select user by primary key. user := &User{Id: user1.Id} err = db.Model(user).WherePK().Select() if err != nil { panic(err) } // Select all users. var users []User err = db.Model(&users).Select() if err != nil { panic(err) } // Select story and associated author in one query. story := new(Story) err = db.Model(story). Relation("Author"). Where("story.id = ?", story1.Id). Select() if err != nil { panic(err) } fmt.Println(user) fmt.Println(users) fmt.Println(story) // Output: User<1 admin [[email protected] [email protected]]> // [User<1 admin [[email protected] [email protected]]> User<2 root [[email protected] roo[email protected]]>] // Story<1 Cool story User<1 admin [[email protected] [email protected]]>>
}
// createSchema creates database schema for User and Story models. func createSchema(db *pg.DB) error { models := []interface{}{ (*User)(nil), (*Story)(nil), }
for _, model := range models { err := db.Model(model).CreateTable(&orm.CreateTableOptions{ Temp: true, }) if err != nil { return err } } return nil
}