Derby和Impala之间的区别

1.德比：
Derby是一个开放源代码关系数据库管理系统。它由Apache Software Foundation在1997年开发。它完全用Java编程语言编写和实现。 Derby的主要数据库模型是Relational DBMS。所有带有Java VM的操作系统都是服务器操作系统。它根据SQL标准为用户提供了细粒度的访问权限，并提供了一个基于占用空间小的标准数据库引擎，该引擎可以紧密地嵌入到任何基于Java的解决方案中。

2.黑斑羚：
Impala是在Hadoop上运行的查询引擎。它是一个开源软件，可以大规模并行处理SQL查询引擎。它支持内存中的数据处理。它开创了Parquet文件格式的使用，Parquet文件格式是一种列式存储布局，已针对数据仓库场景中典型的大规模查询进行了优化。它提供高性能，低延迟的SQL查询，还提供对以Hadoop文件格式存储的数据的交互式查询处理。

Derby和Impala之间的区别：

Derby	Impala
It is developed by Apache Software Foundation in 1997.	It is developed by Cloudera in 2013.
It is written and implemented in Java.	It is written and implemented in SQL.
It provides Immediate Consistency concept.	It provides Eventual Consistency concept.
It support In-memory capabilities.	It do not support In-memory capabilities.
It support ACID Transaction concepts.	No transaction concepts.
It does not support map reduce method.	It support map reduce method.
It does not support Partitioning methods.	It support Sharding Partitioning methods.
It support fine grained access rights according to SQL-standard.	It support access rights for users, groups and roles.
Proprietary protocol using JSON are used as APIs and other access methods.	JDBC and ODBC are used as APIs and access methods.