Hibernate是当前最流行的O/R mapping框架 iBates是另一种优秀的O/R mapping 框架，相对于Hibernate而言 ibates是一种Sql Mapping的ORM实现。 Hibernate对数据接口提供了较为完整的封装 Hibernate的O/R mapping实现了POJO和数据库表之间的映射，以及SQL自动生
Hibernate是当前最流行的O/R mapping框架
iBates是另一种优秀的O/R mapping 框架，相对于Hibernate而言 ibates是一种Sql Mapping的ORM实现。
Hibernate对数据接口提供了较为完整的封装 Hibernate的O/R mapping实现了POJO和数据库表之间的映射，以及SQL自动生成和执行。
程序员甚至不需要对SQL熟练掌握，Hibernate/OJB会根据指导的存储逻辑自动生成对应的SQL语句并调用JDBC接口加以执行。
iBates是对POJO与SQL之间的映射关系，
iBates不会为程序员生成SQL语句，具体SQL需要程序员自己编写，然后通过映射配置文件，将SQL所需的参
数以及返回的结果字段映射到指导的POJO。
相对于Hibernate而言，iBates以SQL开发的工作量和数据库移植性上较差，为系统设计提供了更大的自由空间。
二者对比：
1、iBates非常简单易用，Hibernate相对比较复杂，门槛较高。
2、当系统属于二次开发时，无法对数据库结构做到控制和修改，那么iBates的灵活性将比Hibernate更适合。
3、系统数据处理量巨大，性能要求极为苛刻，这意味着我们必须通过高度优化的SQL语句才能达到性能设计指标，
在这种情况下iBates有更好的可控制性和表现。
4、iBates需要手写SQL语句，Hibernate则基本上是自动生成，偶尔会写一些hql语句。
5、Hibernate现在已成主流的O/R mapping框架，从文档的丰富，成品完善，版本的开发速度都要强于iBates。
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What is the Using temporary status in EXPLAIN and how to avoid it?Apr 15, 2025 am 12:14 AMUsingtemporary indicates that the need to create temporary tables in MySQL queries, which are commonly found in ORDERBY using DISTINCT, GROUPBY, or non-indexed columns. You can avoid the occurrence of indexes and rewrite queries and improve query performance. Specifically, when Usingtemporary appears in EXPLAIN output, it means that MySQL needs to create temporary tables to handle queries. This usually occurs when: 1) deduplication or grouping when using DISTINCT or GROUPBY; 2) sort when ORDERBY contains non-index columns; 3) use complex subquery or join operations. Optimization methods include: 1) ORDERBY and GROUPB
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