檢視数据访问层的原始碼

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|<center>'''数据访问层'''<br><img
src="https://ts1.cn.mm.bing.net/th/id/R-C.f65cd8be4dbdd9e21a776cdd0931a129?rik=qQBgh5JSzx4ELw&riu=http%3a%2f%2fimgconvert.csdnimg.cn%2faHR0cHM6Ly91cGxvYWQtaW1hZ2VzLmppYW5zaHUuaW8vdXBsb2FkX2ltYWdlcy8xNjc2OTg0LWEyYmNiNmRmOGYzNzViNGQucG5n%3fx-oss-process%3dimage%2fformat%2cpng&ehk=jiz%2bESgjfzO%2fN%2f8KTIJLnr0yx8ZfU6CgVZ2fbIgE4QE%3d&risl=&pid=ImgRaw&r=0 " width="280"></center><small>  圖片來自优酷</small> 
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电子与信息技术领域术语
数据库访问层（Data Access Layer）又称为[[DAL层]]，有时候也称为是持久层，其功能主要是负责数据库的访问。简单地说就是实现对数据表的Select（查询）、Insert（插入）、Update（更新）、Delete（删除）等操作。如果要加入ORM的思想，就会包括对象和[[数据表]]之间的映射，以及对象实体的持久化操作。