1. 阿里云云数据库PolarDB：
云数据库PolarDB是一个兼容MySQL、PostgreSQL、Oracle的云原生关系型数据库。云数据库架构在单个集群中支持 5000 台物理机。它专为需要快速性能、高并发和自动扩展的业务关键型数据库应用程序而设计。
2.阿里云日志服务：
日志服务是一个完整的实时数据记录服务。它是由阿里巴巴集团开发的。支持日志的采集、消费、发送、搜索和分析。阿里云PolarDB版与阿里云日志服务的区别：
| S.NO. | Alibaba Cloud ApsaraDB for PolarDB | Alibaba Cloud Log Service |
|---|---|---|
| 1. | It was developed by Alibaba in August 2013. | It was developed by AlibabaCloud Inc. in 2016. |
| 2. | It is a cloud-native relational database compatible with MySQL, PostgreSQL, and Oracle. | It is a complete real-time data logging service that supports collection, consumption, shipping, search, and analysis of logs. |
| 3. | In Alibaba Cloud ApsaraDB for PolarDB there are hosted server operating systems. | In Alibaba Cloud Log Service also there are hosted server operating systems. |
| 4. | The license of Alibaba Cloud ApsaraDB for PolarDB is commercial. | The license of Alibaba Cloud Log Service is also commercial. |
| 5. | It supports XML Format. | It does not support XML Format. |
| 6. | It supports the Server-side scripting. | It does not support the Server-side scripting. |
| 7. | There is only one partitioning method – Sharding. | There is only one partitioning method – Sharding. |
| 8. | It supports SQL query language. | It also supports SQL query language. |
| 9. | It support replication methods. | It support 3 replicas. |
| 10. | ApsaraDB for PolarDB also provides the concept of Referential Integrity. Hence, there are Foreign Keys. | Log Service does not provides the concept of Referential Integrity. Hence, no Foreign Keys. |
| 11. | It supports in-memory capabilities. | It does not support in-memory capabilities. |
| 12. | It does not offer any API for user-defined Map/Reduce methods. | It offers an ES-Hadoop Connector as a Map/Reduce method. |
| 13. | It supports ACID properties. | It does not support ACID properties. |