[Feature] enable self-define MergeEngine

[liming30]

Search before asking

• I searched in the issues and found nothing similar.

Motivation

Currently MergeEngine is defined by paimon. Column-level merge functions can be customized through FieldAggregator, but users cannot customize row-level merge functions. This function mainly supports users to define their row-level merge functions.

Solution

No response

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!

[Stephen0421]

Hello, may I develop this feature?

[liming30]

Hello, may I develop this feature?

@Stephen0421 Thanks, assigned to you.

[Stephen0421]

Hello, may I develop this feature?

@Stephen0421 Thanks, assigned to you.

OK