1. Derby :
Derby is a open source relational database management system. It is developed by Apache Software Foundation in 1997. It is written and implemented completely in the Java programming language. The primary database model of Derby is Relational DBMS. All OS with a Java VM are server operating system. It provides users fine grained access rights according to SQL-standard and with a small-footprint standards-based database engine that can be tightly embedded into any Java based solution.
2. Impala :
Impala is a query engine that runs on Hadoop. It is an open source software and massively parallel processing SQL query engine. It supports in-memory data processing. It is pioneering the use of the Parquet file format, a columnar storage layout that is optimized for large-scale queries typical in data warehouse scenarios. It provides high-performance, low-latency SQL queries and also offers interactive query processing on data stored in Hadoop file formats.
Difference between Derby and 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.|