gistfile1.txt

package main

import (
	"fmt"
	// "log"
	// "time"
	"github.com/go-pg/pg"
	"github.com/go-pg/pg/orm"
)

type Blog struct {
	TableName struct{} `protobuf:"bytes,1,opt,name=tableName" json:"tableName,omitempty" sql:"blog"`
	BlogId    int64    `protobuf:"varint,2,opt,name=blogId,proto3" json:"blogId,omitempty" sql:"blog_id,pk"`
	Url       string   `protobuf:"bytes,3,opt,name=url,proto3" json:"url,omitempty" sql:"url"`
	Places    []*Place `protobuf:"bytes,5,rep,name=places" json:"places,omitempty" pg:",many2many:blog_to_places,fk:blog_id,joinFK:place_id"`
}

type Place struct {
	TableName struct{} `protobuf:"bytes,1,opt,name=tableName" json:"tableName,omitempty" sql:"place"`
	PlaceId   int64    `protobuf:"varint,2,opt,name=placeId,proto3" json:"placeId,omitempty" sql:"place_id,pk"`
	Name      string   `protobuf:"bytes,3,opt,name=name,proto3" json:"name,omitempty" sql:"name"`
}

type BlogToPlace struct {
	BlogId  int
	PlaceId int
}

func createManyToManyTables(db *pg.DB) error {
	models := []interface{}{
		(*Blog)(nil),
		(*Place)(nil),
		(*BlogToPlace)(nil),
	}
	for _, model := range models {
		err := db.CreateTable(model, &orm.CreateTableOptions{
			Temp: true,
		})
		if err != nil {
			return err
		}
	}
	return nil
}

func Connect() *pg.DB {
	db := pg.Connect(&pg.Options{
		User: "postgres",
	})
	db.OnQueryProcessed(func(event *pg.QueryProcessedEvent) {
		query, err := event.FormattedQuery()
		if err != nil {
			panic(err)
		}
		fmt.Println(query)
	})
	return db
}

func main() {
	db := Connect()
	defer db.Close()

	if err := createManyToManyTables(db); err != nil {
		panic(err)
	}

	values := []interface{}{
		&Blog{BlogId: 1, Url: "test1"},
		&Blog{BlogId: 2, Url: "test2"},
		&Place{PlaceId: 1, Name: "test place"},
		&BlogToPlace{BlogId: 1, PlaceId: 1},
		&BlogToPlace{BlogId: 1, PlaceId: 1},
	}
	for _, v := range values {
		err := db.Insert(v)
		if err != nil {
			panic(err)
		}
	}

	// Select order and all items with following queries:
	//
	// SELECT "order"."id" FROM "orders" AS "order" ORDER BY "order"."id" LIMIT 1
	//
	// SELECT order_to_items.*, "item"."id" FROM "items" AS "item"
	// JOIN order_to_items AS order_to_items ON (order_to_items."order_id") IN (1)
	// WHERE ("item"."id" = order_to_items."item_id")

	blog := new(Blog)
	err := db.Model(blog).Relation("Places").First()
	// err := db.Model(place).Select
	if err != nil {
		panic(err)
	}
	fmt.Println("Blog", blog.BlogId, "Places", blog.Places[0].PlaceId)
}