Andy Grove created ARROW-6736: --------------------------------- Summary: [Rust] [DataFusion] Aggregate expressions get evaluated repeatedly Key: ARROW-6736 URL: https://issues.apache.org/jira/browse/ARROW-6736 Project: Apache Arrow Issue Type: Bug Components: Rust, Rust - DataFusion Affects Versions: 0.15.0 Reporter: Andy Grove Assignee: Andy Grove Fix For: 1.0.0
There is a design flaw in the new aggregate expression traits and implementations where the input to the aggregate expression gets evaluated against the whole batch once for each row in the batch. For example, if the batch has 1024 rows then the expression gets evaluated 1024 times instead of once. -- This message was sent by Atlassian Jira (v8.3.4#803005)