[FLINK-15593] add doc to remind users not using Hive aggregate functions in streaming mode

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Invalid
• Component/s: Documentation
• Labels: pull-request-available
• Assignee: Bowen Li
• Reporter: Bowen Li
• Created: 15/Jan/20 05:22
• Updated: 08/Oct/21 09:46
• Resolved: 10/Feb/20 09:40

Description

Note that Hive scalar and table functions implementing UDF, GenericUDF, and GenericUDTF interfaces should be good to run in both
streaming and batch mode in Flink.

Due to that Hive functions are all built for batch processing, aggregate functions in Hive that implement UDAF and GenericUDAFResolver2
interfaces may have unpredictable behaviors when used in streaming mode in Flink. We advice users to only use Hive aggregate functions
interfaces in batch mode.

Issue Links

• is related to: FLINK-15592 Streaming sql throw hive exception when it doesn't use any hive table
• links to: GitHub Pull Request #10857