Ronmi / sdm

Simple tool to map go struct to/from database table

SDM stands for Struct-Database Mapping. It helps you to play with simple Go struct and DB table.

SDM is LIGHTYEARS FAR FROM ORM. It's designed for people who used to write raw SQL.

package main

import (
	"database/sql"
	"log"

	"github.com/Ronmi/sdm"
	_ "github.com/Ronmi/sdm/driver/sqlite3"
	_ "github.com/mattn/go-sqlite3"
)

// Member represents a member in a group
//
// Inline comments are *DEMO*, sqlite3 driver will generate those for you
// when you call CreateTables
type Member struct {
	// CONSTRAINT member_pk PRIMARY KEY (id) AUTOINCREMENT
	ID int `sdm:"id,ai,pri_member_pk"` // id INTEGER

	// CONSTRAINT position UNIQUE (group_id,battle_position)
	GroupID  int    `sdm:"group_id,uniq_position"`        // group_id INTEGER
	Position string `sdm:"battle_position,uniq_position"` // battle_position TEXT
	
	// sqlite doesn't support INDEX constraint, so sad
	ColdDown int    `sdm:"cd,idx_cd"`                     // cd INTEGER
}

// Group represents a group of people
//
// Inline comments are *DEMO*, sqlite3 driver will generate those for you
// when you call CreateTables
type Group struct {
	// CONSTRAINT group_pk PRIMARY KEY (id) AUTOINCREMENT
	ID int `sdm:"id,ai"` // id INTEGER

	// CONSTRAINT group_name UNIQUE (name)
	Name string `sdm:"name,uniq_group_name"` // name TEXT
}

func main() {
	// prepare db connection
	db, err := sql.Open("sqlite3", ":memory:")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	// create sdm
	m := sdm.New(db, sqlite3.New())

	// register types
	m.Reg(Member{}, Group{})

	// create table in db
	m.CreateTables()

	// insert record into table
	if _, err := m.Insert(Group{Name: "Star Force"}); err != nil {
		log.Fatal(err)
	}

	var grp Group
	// make a query
	r := m.Query(grp, `SELECT * FROM 'group'`)
	defer r.Close()

	for r.Next() {
		// scan is so simple
		r.Scan(&grp)
		log.Printf("dump: %#v", grp)
	}
}

License

Copyright(c) 2016-2017 Ronmi Ren (Chung-ping Jen) [e-mail]

MIT