vikunja-api/vendor/xorm.io/xorm/README_CN.md
konrad d28f005552 Update xorm to v1 (#323)
Fix limit for databases other than sqlite

go mod tidy && go mod vendor

Remove unneeded break statements

Make everything work with the new xorm version

Fix xorm logging

Fix lint

Fix redis init

Fix using id field

Fix database init for testing

Change default database log level

Add xorm logger

Use const for postgres

go mod tidy

Merge branch 'master' into update/xorm

# Conflicts:
#	go.mod
#	go.sum
#	vendor/modules.txt

go mod vendor

Fix loading fixtures for postgres

Go mod vendor1

Update xorm to version 1

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/323
2020-04-12 17:29:24 +00:00

14 KiB
Raw Blame History

xorm

English

xorm 是一个简单而强大的Go语言ORM库. 通过它可以使数据库操作非常简便。

Build Status Join the chat at https://img.shields.io/discord/323460943201959939.svg

Notice

v1.0.0 相对于 v0.8.2 有以下不兼容的变更:

  • 移除了部分不符合Go语言命名的函数Id, Sql,请使用 ID, SQL 替代。
  • 删除了对 xorm.io/core 的依赖。大部分代码迁移到了 xorm.io/xorm/core, xorm.io/xorm/names, xorm.io/xorm/schemas 等等几个包中.
  • 重命名了几个结构体,如: core.IMapper -> names.Mapper, core.ILogger -> log.Logger.

特性

  • 支持 Struct 和数据库表之间的灵活映射,并支持自动同步
  • 事务支持
  • 同时支持原始SQL语句和ORM操作的混合执行
  • 使用连写来简化调用
  • 支持使用ID, In, Where, Limit, Join, Having, Table, SQL, Cols等函数和结构体等方式作为条件
  • 支持级联加载Struct
  • Schema支持仅Postgres
  • 支持缓存
  • 通过 xorm.io/reverse 支持根据数据库自动生成 xorm 结构体
  • 支持记录版本(即乐观锁)
  • 通过 xorm.io/builder 内置 SQL Builder 支持
  • 上下文缓存支持
  • 支持日志上下文

驱动支持

目前支持的Go数据库驱动和对应的数据库如下

安装

go get xorm.io/xorm

文档

快速开始

  • 第一步创建引擎driverName, dataSourceName和database/sql接口相同
engine, err := xorm.NewEngine(driverName, dataSourceName)
  • 定义一个和表同步的结构体,并且自动同步结构体到数据库
type User struct {
    Id int64
    Name string
    Salt string
    Age int
    Passwd string `xorm:"varchar(200)"`
    Created time.Time `xorm:"created"`
    Updated time.Time `xorm:"updated"`
}

err := engine.Sync2(new(User))
  • 创建Engine组
dataSourceNameSlice := []string{masterDataSourceName, slave1DataSourceName, slave2DataSourceName}
engineGroup, err := xorm.NewEngineGroup(driverName, dataSourceNameSlice)
masterEngine, err := xorm.NewEngine(driverName, masterDataSourceName)
slave1Engine, err := xorm.NewEngine(driverName, slave1DataSourceName)
slave2Engine, err := xorm.NewEngine(driverName, slave2DataSourceName)
engineGroup, err := xorm.NewEngineGroup(masterEngine, []*Engine{slave1Engine, slave2Engine})

所有使用 engine 都可以简单的用 engineGroup 来替换。

  • Query 最原始的也支持SQL语句查询返回的结果类型为 []map[string][]byte。QueryString 返回 []map[string]string, QueryInterface 返回 []map[string]interface{}.
results, err := engine.Query("select * from user")
results, err := engine.Where("a = 1").Query()

results, err := engine.QueryString("select * from user")
results, err := engine.Where("a = 1").QueryString()

results, err := engine.QueryInterface("select * from user")
results, err := engine.Where("a = 1").QueryInterface()
  • Exec 执行一个SQL语句
affected, err := engine.Exec("update user set age = ? where name = ?", age, name)
  • Insert 插入一条或者多条记录
affected, err := engine.Insert(&user)
// INSERT INTO struct () values ()

affected, err := engine.Insert(&user1, &user2)
// INSERT INTO struct1 () values ()
// INSERT INTO struct2 () values ()

affected, err := engine.Insert(&users)
// INSERT INTO struct () values (),(),()

affected, err := engine.Insert(&user1, &users)
// INSERT INTO struct1 () values ()
// INSERT INTO struct2 () values (),(),()
  • Get 查询单条记录
has, err := engine.Get(&user)
// SELECT * FROM user LIMIT 1

has, err := engine.Where("name = ?", name).Desc("id").Get(&user)
// SELECT * FROM user WHERE name = ? ORDER BY id DESC LIMIT 1

var name string
has, err := engine.Table(&user).Where("id = ?", id).Cols("name").Get(&name)
// SELECT name FROM user WHERE id = ?

var id int64
has, err := engine.Table(&user).Where("name = ?", name).Cols("id").Get(&id)
has, err := engine.SQL("select id from user").Get(&id)
// SELECT id FROM user WHERE name = ?

var valuesMap = make(map[string]string)
has, err := engine.Table(&user).Where("id = ?", id).Get(&valuesMap)
// SELECT * FROM user WHERE id = ?

var valuesSlice = make([]interface{}, len(cols))
has, err := engine.Table(&user).Where("id = ?", id).Cols(cols...).Get(&valuesSlice)
// SELECT col1, col2, col3 FROM user WHERE id = ?
  • Exist 检测记录是否存在
has, err := testEngine.Exist(new(RecordExist))
// SELECT * FROM record_exist LIMIT 1

has, err = testEngine.Exist(&RecordExist{
		Name: "test1",
	})
// SELECT * FROM record_exist WHERE name = ? LIMIT 1

has, err = testEngine.Where("name = ?", "test1").Exist(&RecordExist{})
// SELECT * FROM record_exist WHERE name = ? LIMIT 1

has, err = testEngine.SQL("select * from record_exist where name = ?", "test1").Exist()
// select * from record_exist where name = ?

has, err = testEngine.Table("record_exist").Exist()
// SELECT * FROM record_exist LIMIT 1

has, err = testEngine.Table("record_exist").Where("name = ?", "test1").Exist()
// SELECT * FROM record_exist WHERE name = ? LIMIT 1
  • Find 查询多条记录当然可以使用Join和extends来组合使用
var users []User
err := engine.Where("name = ?", name).And("age > 10").Limit(10, 0).Find(&users)
// SELECT * FROM user WHERE name = ? AND age > 10 limit 10 offset 0

type Detail struct {
    Id int64
    UserId int64 `xorm:"index"`
}

type UserDetail struct {
    User `xorm:"extends"`
    Detail `xorm:"extends"`
}

var users []UserDetail
err := engine.Table("user").Select("user.*, detail.*")
    Join("INNER", "detail", "detail.user_id = user.id").
    Where("user.name = ?", name).Limit(10, 0).
    Find(&users)
// SELECT user.*, detail.* FROM user INNER JOIN detail WHERE user.name = ? limit 10 offset 0
  • IterateRows 根据条件遍历数据库,可以有两种方式: Iterate and Rows
err := engine.Iterate(&User{Name:name}, func(idx int, bean interface{}) error {
    user := bean.(*User)
    return nil
})
// SELECT * FROM user

err := engine.BufferSize(100).Iterate(&User{Name:name}, func(idx int, bean interface{}) error {
    user := bean.(*User)
    return nil
})
// SELECT * FROM user Limit 0, 100
// SELECT * FROM user Limit 101, 100

rows, err := engine.Rows(&User{Name:name})
// SELECT * FROM user
defer rows.Close()
bean := new(Struct)
for rows.Next() {
    err = rows.Scan(bean)
}
  • Update 更新数据除非使用Cols,AllCols函数指明默认只更新非空和非0的字段
affected, err := engine.ID(1).Update(&user)
// UPDATE user SET ... Where id = ?

affected, err := engine.Update(&user, &User{Name:name})
// UPDATE user SET ... Where name = ?

var ids = []int64{1, 2, 3}
affected, err := engine.In(ids).Update(&user)
// UPDATE user SET ... Where id IN (?, ?, ?)

// force update indicated columns by Cols
affected, err := engine.ID(1).Cols("age").Update(&User{Name:name, Age: 12})
// UPDATE user SET age = ?, updated=? Where id = ?

// force NOT update indicated columns by Omit
affected, err := engine.ID(1).Omit("name").Update(&User{Name:name, Age: 12})
// UPDATE user SET age = ?, updated=? Where id = ?

affected, err := engine.ID(1).AllCols().Update(&user)
// UPDATE user SET name=?,age=?,salt=?,passwd=?,updated=? Where id = ?
  • Delete 删除记录需要注意删除必须至少有一个条件否则会报错。要清空数据库可以用EmptyTable
affected, err := engine.Where(...).Delete(&user)
// DELETE FROM user Where ...

affected, err := engine.ID(2).Delete(&user)
// DELETE FROM user Where id = ?
  • Count 获取记录条数
counts, err := engine.Count(&user)
// SELECT count(*) AS total FROM user
  • Sum 求和函数
agesFloat64, err := engine.Sum(&user, "age")
// SELECT sum(age) AS total FROM user

agesInt64, err := engine.SumInt(&user, "age")
// SELECT sum(age) AS total FROM user

sumFloat64Slice, err := engine.Sums(&user, "age", "score")
// SELECT sum(age), sum(score) FROM user

sumInt64Slice, err := engine.SumsInt(&user, "age", "score")
// SELECT sum(age), sum(score) FROM user
  • 条件编辑器
err := engine.Where(builder.NotIn("a", 1, 2).And(builder.In("b", "c", "d", "e"))).Find(&users)
// SELECT id, name ... FROM user WHERE a NOT IN (?, ?) AND b IN (?, ?, ?)
  • 在一个Go程中多次操作数据库但没有事务
session := engine.NewSession()
defer session.Close()

user1 := Userinfo{Username: "xiaoxiao", Departname: "dev", Alias: "lunny", Created: time.Now()}
if _, err := session.Insert(&user1); err != nil {
    return err
}

user2 := Userinfo{Username: "yyy"}
if _, err := session.Where("id = ?", 2).Update(&user2); err != nil {
    return err
}

if _, err := session.Exec("delete from userinfo where username = ?", user2.Username); err != nil {
    return err
}

return nil
  • 在一个Go程中有事务
session := engine.NewSession()
defer session.Close()

// add Begin() before any action
if err := session.Begin(); err != nil {
    // if returned then will rollback automatically
    return err
}

user1 := Userinfo{Username: "xiaoxiao", Departname: "dev", Alias: "lunny", Created: time.Now()}
if _, err := session.Insert(&user1); err != nil {
    return err
}

user2 := Userinfo{Username: "yyy"}
if _, err := session.Where("id = ?", 2).Update(&user2); err != nil {
    return err
}

if _, err := session.Exec("delete from userinfo where username = ?", user2.Username); err != nil {
    return err
}

// add Commit() after all actions
return session.Commit()
  • 事务的简写方法
res, err := engine.Transaction(func(session *xorm.Session) (interface{}, error) {
    user1 := Userinfo{Username: "xiaoxiao", Departname: "dev", Alias: "lunny", Created: time.Now()}
    if _, err := session.Insert(&user1); err != nil {
        return nil, err
    }

    user2 := Userinfo{Username: "yyy"}
    if _, err := session.Where("id = ?", 2).Update(&user2); err != nil {
        return nil, err
    }

    if _, err := session.Exec("delete from userinfo where username = ?", user2.Username); err != nil {
        return nil, err
    }
    return nil, nil
})
  • 上下文缓存,如果启用,那么针对单个对象的查询将会被缓存到系统中,可以被下一个查询使用。
	sess := engine.NewSession()
	defer sess.Close()

	var context = xorm.NewMemoryContextCache()

	var c2 ContextGetStruct
	has, err := sess.ID(1).ContextCache(context).Get(&c2)
	assert.NoError(t, err)
	assert.True(t, has)
	assert.EqualValues(t, 1, c2.Id)
	assert.EqualValues(t, "1", c2.Name)
	sql, args := sess.LastSQL()
	assert.True(t, len(sql) > 0)
	assert.True(t, len(args) > 0)

	var c3 ContextGetStruct
	has, err = sess.ID(1).ContextCache(context).Get(&c3)
	assert.NoError(t, err)
	assert.True(t, has)
	assert.EqualValues(t, 1, c3.Id)
	assert.EqualValues(t, "1", c3.Name)
	sql, args = sess.LastSQL()
	assert.True(t, len(sql) == 0)
	assert.True(t, len(args) == 0)

贡献

如果您也想为Xorm贡献您的力量请查看 CONTRIBUTING。您也可以加入QQ群 技术帮助和讨论。 群一280360085 (已满) 群二795010183

Credits

Contributors

感谢所有的贡献者. [Contribute].

Backers

感谢我们所有的 backers! 🙏 [成为 backer]

Sponsors

成为 sponsor 来支持 xorm。您的 logo 将会被显示并被链接到您的网站。 [成为 sponsor]

案例

更新日志

请访问 CHANGELOG.md 获得更新日志。

LICENSE

BSD License http://creativecommons.org/licenses/BSD/