[Feature] Add distinct parameter support to FieldListaggAgg operator

[759434091]

Search before asking

• [x] I searched in the issues and found nothing similar.

Motivation

Users often store complex data such as user1, user2, user3 as simple string rather then complex date type (map,array). When aggregating these fields, there is currently no support for deduplication set.add.

Solution

Add a distinct option support to FieldListAgg?

Anything else?

This approach works fine for user1,user2,user3, but it's insufficient for kv-string deduplication k1=v1;k2=v2. I'm not sure whether to handle this with string manipulation or a map-merge aggregation approach due to performance concerns..

Are you willing to submit a PR?

• [ ] I'm willing to submit a PR!