forked from mirror/gorm
148 lines
4.1 KiB
Markdown
148 lines
4.1 KiB
Markdown
# GORM
|
|
|
|
Yet Another ORM library for Go, aims for developer friendly
|
|
|
|
## Basic Usage
|
|
|
|
```go
|
|
db, _ = Open("postgres", "user=gorm dbname=gorm sslmode=disable")
|
|
|
|
type User struct {
|
|
Id int64
|
|
Age int64
|
|
Birthday time.Time
|
|
Name string
|
|
CreatedAt time.Time
|
|
UpdatedAt time.Time
|
|
}
|
|
|
|
// Create
|
|
user = User{Name: "jinzhu", Age: 18, Birthday: time.Now())
|
|
db.Save(&user)
|
|
|
|
// Update
|
|
user.Name = "jinzhu 2"
|
|
db.Save(&user)
|
|
|
|
// Delete
|
|
db.Delete(&user)
|
|
|
|
// Get First matched record
|
|
db.Where("name = ?", "jinzhu").First(&user)
|
|
|
|
// Get All matched records
|
|
db.Where("name = ?", "jinzhu").Find(&users)
|
|
|
|
// Advanced Where Usage
|
|
db.Where("name <> ?", "jinzhu").Find(&users)
|
|
db.Where("name = ? and age >= ?", "3", "22").Find(&users)
|
|
db.Where("name in (?)", []string["jinzhu", "jinzhu 2"]).Find(&users)
|
|
db.Where("birthday < ?", time.Now()).Find(&users)
|
|
|
|
// Inline search condition
|
|
db.First(&user, 23) // select * from users where id = 23 limit 1;
|
|
db.First(&user, "name = ?", "jinzhu") // select * from users where name = "jinzhu" limit 1;
|
|
db.Find(&users, "name = ?", "jinzhu") // select * from users where name = "jinzhu";
|
|
db.Find(&users, "name <> ? and age > ?", "jinzhu", 20) // select * from users where name <> "jinzhu" and age > 20;
|
|
|
|
// Select
|
|
db.Select("name").Find(&users)
|
|
|
|
// Order
|
|
db.Order("age desc, name").Find(&users)
|
|
db.Order("age desc").Order("name").Find(&users)
|
|
|
|
// Limit
|
|
db.Limit(3).Find(&users)
|
|
db.Limit(10).Find(&ten_users).Limit(20).Find(&twenty_users).Limit(-1).Find(&all_users)
|
|
|
|
// Offset
|
|
db.Offset(3).Find(&users)
|
|
db.Offset(10).Find(&users).Offset(20).Find(&users).Offset(-1).Find(&users)
|
|
|
|
// Or
|
|
db.Where("role = ?", "admin").Or("role = ?", "super_admin").Find(&users)
|
|
|
|
// Count
|
|
db.Where("name = ?", "jinzhu").Or("name = ?", "jinzhu 2").Find(&users).Count(&count)
|
|
db.Model(&User{}).Where("name = ?", "jinzhu").Count(&count)
|
|
|
|
// CreatedAt (auto insert current time on create)
|
|
If your struct has field CreatedAt,
|
|
it will be filled with the current time when insert into database
|
|
|
|
// UpdatedAt (auto update the time on save)
|
|
If your struct has field UpdatedAt,
|
|
it will be filled with the current time when update it
|
|
|
|
// Callbacks
|
|
Below callbacks are defined now:
|
|
|
|
`BeforeCreate`, `BeforeUpdate`, `BeforeSave`, `AfterCreate`, `AfterUpdate`, `AfterSave`
|
|
`BeforeDelete`, `AfterDelete`
|
|
|
|
Callbacks is a function defined to a model, if the function return error, will prevent the database operations.
|
|
|
|
func (u *User) BeforeUpdate() (err error) {
|
|
if u.readonly() {
|
|
err = errors.New("Read Only User")
|
|
}
|
|
return
|
|
}
|
|
|
|
// Pluck (get users's age as map)
|
|
var ages []int64
|
|
db.Find(&users).Pluck("age", &ages)
|
|
var names []string
|
|
db.Model(&User{}).Pluck("name", &names)
|
|
|
|
// Query Chains
|
|
db.Where("name <> ?", "jinzhu").Where("age >= ? and role <> ?", 20, "admin").Find(&users)
|
|
|
|
// Create Table with struct
|
|
db.CreateTable(&User{})
|
|
|
|
// Run Raw SQL
|
|
db.Exec("drop table users;")
|
|
```
|
|
|
|
## Cool Examples
|
|
|
|
```go
|
|
// Already excited about the basic usage? Let's see some magic!
|
|
|
|
db.First(&first_article).Count(&total_count).Limit(10).Find(&first_page_articles).Offset(10).Find(&second_page_articles)
|
|
// first_article return the latest article
|
|
// total_count return the total numbers of articles
|
|
// first_page_articles return the latest 10 articles
|
|
// second_page_articles return the latest 10 to 20 articles
|
|
|
|
db.Where("created_at > ?", "2013/10/10").Find(&cancelled_orders, "state = ?", "cancelled").Find(&shipped_orders, "state = ?", "shipped")
|
|
// cancelled_orders return all cancelled orders since 2013/10/10
|
|
// shipped_orders return all shipped orders since 2013/10/10
|
|
|
|
db.Model(&Order{}).Where("amount > ?", 10000).Pluck("user_id", &paid_user_ids)
|
|
db.Where("user_id = ?", paid_user_ids).Find(&:paid_users)
|
|
|
|
db.Where("product_name = ?", "fancy_product").Find(&orders).Find(&shopping_cart)
|
|
|
|
// Open your mind, add more cool examples
|
|
```
|
|
|
|
## TODO
|
|
* Update, Updates like rails's update_attribute, update_attributes
|
|
* Soft Delete
|
|
* Query with map or struct
|
|
* FindOrInitialize / FindOrCreate
|
|
* SQL Log
|
|
* Auto Migration
|
|
* Index, Unique, Valiations
|
|
|
|
# Author
|
|
|
|
**Jinzhu**
|
|
|
|
* <http://github.com/jinzhu>
|
|
* <wosmvp@gmail.com>
|
|
* <http://twitter.com/zhangjinzhu>
|