chaoyli commented on issue #3288: Fix bug when use ZoneMap/BloomFiter on column 
with REPLACE/REPLACE_IF_NOT_NULL
URL: https://github.com/apache/incubator-doris/pull/3288#issuecomment-611419945
 
 
   > If this optimization is removed, some query will suffer a performance 
degradation.
   > When the scanned value column type is all REPLACE, it seems that this 
optimization can be applied.
   > Can you leave this optimization for this case?
   
   I think it's a very corner case to select all columns on REPLACE and will 
waste much resource.
   1. Only base rowset(version starts with zero) can use it, all other rowsets 
have to save ZoneMap/BloomFilter for REPLACE columns, which is non-sense.
   2. REPLACE is value column, the ZoneMap is not very useful because of sorted 
column is key column.

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