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Can SQL evolution be done without starting from scratch?

I'm trying to understand how SQL evolution works. Assume we have some SQL, and want to slightly modify it (for instance - add one more column to be calculated, or something). Is it possible to do in a way that the existing state is saved? Or such a change means we must start from scratch? Any pointers to existing docs if any are highly appreciated!

Iv

Ivan Burmistrov

Asked on Sep 07, 2023

  1. Schema evolution is considered as the precondition for SQL evolution. It is possible to add a column to a table without starting from scratch.
  2. Decoupling the streaming query and its result table allows for maintaining old and new stream queries in the same result table for a short time.
  3. Altering materialized views' SQL directly can be done in special cases like adding aggregation functions, union clauses, or predicates, allowing the new streaming query job to reuse the old state and continue computing.
Sep 07, 2023Edited by