yangyichao-mango opened a new issue, #2477: URL: https://github.com/apache/doris-website/issues/2477
Page Link: https://doris.apache.org/zh-CN/docs/query-acceleration/materialized-view/async-materialized-view/use-guide#%E7%89%A9%E5%8C%96%E8%A7%86%E5%9B%BE%E5%88%B7%E6%96%B0%E6%96%B9%E5%BC%8F%E9%80%89%E6%8B%A9%E5%8E%9F%E5%88%99 Reason: I can understand that the large cardinality of the fields in the text will lead to poor aggregation effects in materialized views, but the calculation logic for the numbers given in the text is incorrect. The reason is that the data volume before aggregation is 1,000,000, and the data volume after aggregation is the product of the cardinality of the three fields, which is 100 x 50 x 3500 = 17,000,000. However, it is obvious that the amount of data after aggregation will not exceed the amount of data before aggregation.（我能理解文中想表达字段的基数比较大，会导致物化视图的聚合效果变差，但是文中给的数字的计算逻辑有误。原因是：聚合前的数据量为1000000，文中想表达聚合后的数据量是3个字段的基数相乘，也就是100x50x3500=17000000。但是明显，聚合后的数据量是不会超过聚合前的数据量的。） Suggest: （我建议内容改为：“比如 c 的基数是 3500，那么聚合后的数据量会趋近1000000（统计逻辑：聚合前的数据量为1000000，聚合后的理论最大数据量是3个字段的基数相乘，也就是100x50x3500=17000000，但是聚合后的数据量不会超过聚合前的数据量的，因此聚合后数据量趋近1000000），构建这样的物化视图性能加速收益低。”） BTW, May I contribute to this pull request? Our company has been frequently using Doris lately. If given the chance, I would also like to gradually become involved in the community.  -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
