Github user fhueske commented on the issue:

    https://github.com/apache/flink/pull/4183
  
    I think support for watermark configuration in a DDL statement is a nice 
feature but not a replacement for this parameter.
    
    I am thinking of a use case where streaming tables are registered in a 
catalog. Each table has some kind of watermark strategy which might be 
conservative (little late data, higher latency) or eager (more late data, less 
latency). Users want to query these streaming tables but might need more 
conservative or more eager watermarks. Of course they don't want to register 
the tables again (with all the additional information required) to just adapt 
the watermarks for their use case. With this parameter, they can simply adjust 
the watermarks of the already registered tables.
    
    While writing this, I noticed that it would make sense to optionally add 
the name of table on which the watermark manipulation should be applied. Some 
table might already have good watermarks while others need to be adjusted.
    So we would have two configuration methods:
    
    ```
    // adjusts the watermarks of all input tables
     def withLateDataTimeOffset(lateDataTimeOffset: Time): StreamQueryConfig
    
    // adjusts the watermarks of a specific input table
     def withLateDataTimeOffset(table: String, lateDataTimeOffset: Time): 
StreamQueryConfig
    ```
    
    What do you think @sunjincheng121 and @wuchong?


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