kazdy opened a new issue, #7282:
URL: https://github.com/apache/hudi/issues/7282

   **Describe the problem you faced**
   
   In the community I see increasing number of users interested in being able 
to update records on tables without precombine filed.
   Flink supports `public static final String NO_PRE_COMBINE = 
"no_precombine";` (although not documented) for inserts and updates:
   
https://github.com/apache/hudi/blob/3109d890f13b1b29e5796a9f34ab28fa898ec23c/hudi-flink-datasource/hudi-flink/src/main/java/org/apache/hudi/configuration/FlinkOptions.java#L98
   
   This was Introduced by https://github.com/apache/hudi/pull/3874.
   https://issues.apache.org/jira/browse/HUDI-2633
   
   `When the precombine field is not specified, we use the proctime semantics, 
that means, the records come later are more fresh`
   
   There's argument against it, because for updates records cannot be 
deduplicated properly. But at the same time Hudi allows us to use non-strict 
insert mode that breaks PK uniqueness. 
   Users can make informed decision and handle duplicates on their own or bring 
in their own precombine logic with window functions etc.
   
   At least Flink case shows it surely can be done.
   
   I'm willing to contribute but need some guidance.
   
   **To Reproduce**
   
   Steps to reproduce the behavior:
   
   1. create table without precombine key
   2. insert records
   3. update records (or merge into)
   4. delete records
   Constraints:
   Once disabled, precombine field cannot be enabled.
   Once enabled, precombine field cannot be disabled.
   Users might end up with duplicated data using this feature.
   
   **Expected behavior**
   
   Table without precombine  field specifiec allows users to insert, update, 
delete data.
   
   **Environment Description**
   
   * Hudi version : 0.12.1
   
   * Spark version : 3.3
   
   * Hive version : none
   
   * Hadoop version : none
   
   * Storage (HDFS/S3/GCS..) : none
   
   * Running on Docker? (yes/no) : none
   
   
   **Additional context**
   
   https://apache-hudi.slack.com/archives/C4D716NPQ/p1669138583694699
   https://apache-hudi.slack.com/archives/C4D716NPQ/p1667676225456149
   
https://apache-hudi.slack.com/archives/C4D716NPQ/p1661521804381729?thread_ts=1661445128.731389&cid=C4D716NPQ
   
   
   **Stacktrace**
   na
   
   


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