随笔分类 - ODB

15 Advanced Techniques and Mechanisms ODB高级技术和机制

摘要：15.1 Transaction Callbacks 事务回调 The ODB transaction class (odb::transaction) allows an application to register a callback that will be called after th 阅读全文

posted @ 2022-02-23 14:10 菜鸟_IceLee 阅读(115) 评论(0) 推荐(0) 编辑

13 Database Schema Evolution ODB数据库模式演变

摘要：When we add new persistent classes or change the existing ones, for example, by adding or deleting data members, the database schema necessary to stor 阅读全文

posted @ 2022-02-22 15:08 菜鸟_IceLee 阅读(189) 评论(0) 推荐(0) 编辑

3 Working with Persistent Objects ODB使用持久对象

摘要：The previous chapters gave us a high-level overview of ODB and showed how to use it to store C++ objects in a database. In this chapter we will examin 阅读全文

posted @ 2022-02-17 11:46 菜鸟_IceLee 阅读(308) 评论(0) 推荐(0) 编辑

14 ODB Pragma Language ODB编程语言

摘要：As we have already seen in previous chapters, ODB uses a pragma-based language to capture database-specific information about C++ types. This chapter 阅读全文

posted @ 2022-02-16 11:41 菜鸟_IceLee 阅读(293) 评论(0) 推荐(0) 编辑

12 Optimistic Concurrency ODB 乐观并发

摘要：The ODB transaction model (Section 3.5, "Transactions") guarantees consistency as long as we perform all the database operations corresponding to a sp 阅读全文

posted @ 2022-02-11 11:27 菜鸟_IceLee 阅读(81) 评论(0) 推荐(0) 编辑

6 ODB Relationships ODB依赖关系

摘要：6 Relationships 依赖关系 Relationships between persistent objects are expressed with pointers or containers of pointers. The ODB runtime library provides 阅读全文

posted @ 2022-01-14 14:11 菜鸟_IceLee 阅读(301) 评论(0) 推荐(0) 编辑

4 ODB Querying the Database ODB数据库查询

摘要：If we don't know the identifiers of the objects that we are looking for, we can use queries to search the database for objects matching certain criter 阅读全文

posted @ 2022-01-13 09:18 菜鸟_IceLee 阅读(512) 评论(0) 推荐(0) 编辑

11 ODB Session 会话

摘要：A session is an application's unit of work that may encompass several database transactions. In this version of ODB a session is just an object cache. 阅读全文

posted @ 2022-01-10 10:09 菜鸟_IceLee 阅读(122) 评论(0) 推荐(0) 编辑

10 ODB Views 视图

摘要：An ODB view is a C++ class or struct type that embodies a light-weight, read-only projection of one or more persistent objects or database tables or t 阅读全文

posted @ 2022-01-10 10:00 菜鸟_IceLee 阅读(198) 评论(0) 推荐(0) 编辑

9 ODB Sections

摘要：ODB sections are an optimization mechanism that allows us to partition data members of a persistent class into groups that can be separately loaded an 阅读全文

posted @ 2022-01-10 09:21 菜鸟_IceLee 阅读(110) 评论(0) 推荐(0) 编辑

8 ODB 继承（Inheritance）

摘要：In C++ inheritance can be used to achieve two different goals. We can employ inheritance to reuse common data and functionality in multiple classes. F 阅读全文

posted @ 2022-01-10 09:06 菜鸟_IceLee 阅读(142) 评论(0) 推荐(0) 编辑

7 ODB 值类型（Value Types）

摘要：In Section 3.1, "Concepts and Terminology" we have already discussed the notion of values and value types as well as the distinction between simple an 阅读全文

posted @ 2021-12-24 10:23 菜鸟_IceLee 阅读(168) 评论(0) 推荐(0) 编辑

5 可供ODB使用的标准容器（5 Containers）

摘要：5 Containers 容器 The ODB runtime library provides built-in persistence support for all the commonly used standard C++98/03 containers, namely, std::vec 阅读全文

posted @ 2021-12-24 09:23 菜鸟_IceLee 阅读(312) 评论(0) 推荐(0) 编辑