标签：des style blog ar color os 使用 sp for
1、创建engine
engine, err := xorm.NewEngine(driverName, dataSourceName)
上述代码创建了一个数据库引擎，可以在一个程序中创建多个engine。
2、查询方法：
2.1、支持sql查询：
1、查询一个string类型的sql，返回[]map[string][]byte类型的切片（查询）
results, err := engine.Query("select * from user")
2、执行一个string的sql，返回结果影响行数（增删改）
affected, err := engine.Exec("update user set .... where ...")
2.2、ORM方法：
主要有七个方法和其他辅助的方法来操作数据库。
1、插入一个或者多个数据：
affected, err := engine.Insert(&struct) // INSERT INTO struct () values () affected, err := engine.Insert(&struct1, &struct2) // INSERT INTO struct1 () values () // INSERT INTO struct2 () values () affected, err := engine.Insert(&sliceOfStruct) // INSERT INTO struct () values (),(),() affected, err := engine.Insert(&struct1, &sliceOfStruct2) // INSERT INTO struct1 () values () // INSERT INTO struct2 () values (),(),()
2、从数据库里面查询一条记录：
has, err := engine.Get(&user) // SELECT * FROM user LIMIT 1
3、从数据库中查询多条记录：
sliceOfStructs := new(Struct) err := engine.Find(sliceOfStructs) // SELECT * FROM user
4、查询多条记录，然后每条记录进行处理，有两个方法，一个是iterator，另一个是raw：
err := engine.Iterate(...) // SELECT * FROM user raws, err := engine.Raws(...) // SELECT * FROM user bean := new(Struct) for raws.Next() { err = raws.Scan(bean) }
5、更新一条或者多条记录：
affected, err := engine.Update(&user) // UPDATE user SET ...
6：删除一条或者多条记录，必须存在删除条件
affected, err := engine.Where(...).Delete(&user) // DELETE FROM user Where ...
7、查询记录条数:
counts, err := engine.Count(&user) // SELECT count(*) AS total FROM user
2.3：条件：
1、Id、In：
engine.Id(1).Get(&user) // for single primary key // SELECT * FROM user WHERE id = 1 engine.Id(core.PK{1, 2}).Get(&user) // for composite primary keys // SELECT * FROM user WHERE id1 = 1 AND id2 = 2 engine.In("id", 1, 2, 3).Find(&users) // SELECT * FROM user WHERE id IN (1, 2, 3) engine.In("id", []int{1, 2, 3}) // SELECT * FROM user WHERE id IN (1, 2, 3)
2、 Where, And, Or
engine.Where().And().Or().Find() // SELECT * FROM user WHERE (.. AND ..) OR ...
3、OrderBy, Asc, Desc
engine.Asc().Desc().Find() // SELECT * FROM user ORDER BY .. ASC, .. DESC engine.OrderBy().Find() // SELECT * FROM user ORDER BY ..
4、 Limit, Top
engine.Limit().Find() // SELECT * FROM user LIMIT .. OFFSET .. engine.Top(5).Find() // SELECT TOP 5 * FROM user // for mssql // SELECT * FROM user LIMIT .. OFFSET 0 //for other databases
5、Sql, 查询原生SQL
engine.Sql("select * from user").Find()
6、Cols, Omit, Distinct
engine.Cols("col1, col2").Find()
// SELECT col1, col2 FROM user
engine.Cols("col1", "col2").Where().Update(user)
// UPDATE user set col1 = ?, col2 = ? Where ...
engine.Omit("col1").Find()
// SELECT col2, col3 FROM user
engine.Omit("col1").Insert()
// INSERT INTO table (non-col1) VALUES ()
engine.Distinct("col1").Find()
// SELECT DISTINCT col1 FROM user
7、Join, GroupBy, Having
engine.GroupBy("name").Having("name=‘xlw‘").Find()
//SELECT * FROM user GROUP BY name HAVING name=‘xlw‘
engine.Join("LEFT", "userdetail", "user.id=userdetail.id").Find()
//SELECT * FROM user LEFT JOIN userdetail ON user.id=userdetail.id
标签：des style blog ar color os 使用 sp for
原文地址：http://www.cnblogs.com/guhao123/p/4159688.html
