xorm速記卡 Quick Reference

xorm is a very famous golang lib, for operating relation database.

Install

go get -v github.com/go-xorm/xorm

Documentation

• godoc-xorm
• gowalker-xorm
• Quickstart

Get started

Import packages

package main

import (
	"log"

	"github.com/go-xorm/xorm"
	_ "github.com/mattn/go-sqlite3"
)

Define models

type User struct {
	Id    int64
	Name  string `xorm:"unique"`
	Email string
}

Create database engine

var xe *xorm.Engine

func init() {
	var err error
	xe, err = xorm.NewEngine("sqlite3", "./test.db")
	if err != nil {
		log.Fatal(err)
	}
	if err = xe.Sync(&User{}); err != nil {
		log.Fatal(err)
	}
}

Insert and Query

func main() {
	xe.Insert(&User{Name: "UU", Email: "uu@example.com"})

	var user = &User{Name: "UU"}
	exists, err := xe.Get(user)
	if err != nil {
		log.Fatal(err)
	}
	log.Printf("Exists: %v, User: %#v", exists, user)
}

Driver and source

Example

x, err := xorm.NewEngine("mysql", "root:123@/test?charset=utf8")
defer x.Close()

other driver

mysql github.com/go-sql-driver/mysql

[username[:password]@][protocol[(address)]]/dbname[?param1=value1&...&paramN=valueN]

mymysql github.com/ziutek/mymysql/godrv

usage todo.

postgresql github.com/lib/pq

1. postgres://username:password@address/dbname?sslmode=verify-full
2. user=pqgotest dbname=pqgotest sslmode=verify-full

sqlite3 github.com/mattn/go-sqlite3

1. ./dbfile

Define models

// default matches
// - string => varchar(255)
type Model struct {
	Id         int64
	SmallInt   int64     `xorm:"smallint"`
	Int        int64     `xorm:"int"`
	Text       string    `xorm:"text"`
	DefaultVal int64     `xorm:"default 3"`
	Bool       bool      `xorm:"bool"`
	Unique     string    `xorm:"unique"`    // unique([Unique])
	UniqA1     string    `xorm:"unique(a)"` // unique([UniqA1, UniqA2])
	UniqA2     string    `xorm:"unique(a)"`
	Version    int64     `xorm:"version"` // will be filled 1 on insert and autoincr on update
	CreatedAt  time.Time `xorm:"created"` // will be filled in current time on insert
	UpdatedAt  time.Time `xorm:"updated"` // will be filled in current time on insert or update
}

column types

ref: https://github.com/lunny/xorm/blob/master/docs/COLUMNTYPE.md

• pk # primary key
• autoincr
• [not ]null
• unique or unique(uniquename)
• index or index(indexname)
• extends
• `- # ignore this field
• created # This field will be filled in current time on insert
• version # This field will be filled 1 on insert and autoincrement on update
• default 0 # default value, need quoted if it is a string

CRUD funcs

Create, Retrive, Update, Delete

INSERT (Create) more

• Insert one record

  user := &User{
      Name: "test",
  }
  affected, err := engine.Insert(user)

• Insert multi records

  users := make([]User, 0)
  users = append(users, User{Name: "test"})
  affected, err := engine.Insert(&users)

Query (Retrieve) more

• Get one record

  var user = User{Id: 1}
  has, err := engine.Get(&user)

• Fetch multi records in to slice or map

  var everyone []User
  err := engine.Find(&everyone)
  
  users := make(map[int64]User)
  err := engine.Find(&users)

• Use where and limit

  var users []User
  err := engine.Where("id > ?", 3).Limit(10, 5).Find(&users) // limit 10 offset 5

• Query use struct

  var users []User
  err := engine.Find(&users, &User{School: "hangzhou"})

• Use in function

  var users []User
  err := engine.In("id", 1, 3, 5).Find(&users)

• Default will query all cols, use Cols to restrict that

  var users []User
  err := engine.Cols("id", "name").Find(&users)

• Count

  total, err := engine.Where("id > ?", 1).Count(&User{})

  If user is not empty, it will become the select rule.

  total, err := engine.Count(&User{School: "hangzhou"})

• Complex example

  var users []User
  err = x.Cols("age", "name")
      .Where("`age` > ?", 10)
      .And("`age` < 30")
      .Limit(10, 5) // limit 10 offset 5
      .Desc("age")
      .In("school", "hangzhou", "beijing"})
      .Find(&users)

Update (Update) more