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Co-authored-by: Lauris BH <lauris@nix.lv> Co-authored-by: techknowlogick <techknowlogick@gitea.io>
14 KiB
Vendored
14 KiB
Vendored
xorm
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。
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,如
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:
-
MsSql
-
Oracle
- github.com/mattn/go-oci8 (试验性支持)
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
Iterate
和Rows
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/