5.CRUD操作:
CRUD(即Create, Retrieve, Update, Delete方法)是数据库的基本操作,很多程序员早期可能一直重复着这些简单后又枯草的工作。ORM最大的贡献就是把程序员从这种状态中解脱出来,而把精力集中于业务实体对象的设计。
(1)实体类的创建、更新和删除
Snake.Net通过ObjectManager对象实现与数据库的持久工作, ObjectManager使用Save和Delete方法实现业务实体对象的创建、更新和删除。请看下列代码:
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(2)使用存储过程来实现创建、更新和删除
默认情况下,Snake.Net根据业务实体对象与数据表结构的映射,自动生成SQL语句,并进行操作。但是根据需要,用户可以通过配置文件利用存储过程,实现创建、更新和删除操作。参见下面的配置节点,Snake.Net可以通过设置insertProcedure, updateProcedure和deleteProcedure三个配置节点,用于执行指定的存储过程操作。
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图 5-2-1 配置存储过程名称
(3)事务处理
Snake.Net有两种方法实现事务处理,一种是使用ObjectManager的事务处理方法:BeginTransaction、Commit和 Abort,请参见以下代码:
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另一种方法是使用TransactionContext类,调用事务环境进行事务处理,请参见以下代码:
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(4)接受业务实体
Snake.Net可以通过ObjectManager的Retrieve和List方法用于接受业务实体对象,前者可根据关键字接受单个的业务实体,后者可以根据一组关键字接受一组业务实体。请参看以下代码:
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