Jefffrey opened a new issue, #7024:
URL: https://github.com/apache/arrow-rs/issues/7024

   Something interesting about the rank function in arrow-rs is that it seems 
to behave differently compared to others.
   
   Postgres:
   
   > rank () → bigint
   > Returns the rank of the current row, with gaps; that is, the row_number of 
the first row in its peer group.
   
   - https://www.postgresql.org/docs/current/functions-window.html
   
   DuckDB:
   
   > Description        The rank of the current row with gaps; same as 
row_number of its first peer.
   
   - https://duckdb.org/docs/sql/functions/window_functions.html#rank
   
   SQL Server:
   
   > If two or more rows tie for a rank, each tied row receives the same rank. 
For example, if the two top salespeople have the same SalesYTD value, they are 
both ranked one.
   
   - 
https://learn.microsoft.com/en-us/sql/t-sql/functions/rank-transact-sql?view=sql-server-ver16
   
   It seems these other ones would have ties take the lower values, whereas for 
arrow-rs the existing rank function (and subsequently what is introduced here) 
takes the higher value; I guess this might be worth a broader discussion, as 
this PR itself currently follows the existing behaviour
   
   :thinking:
   
   _Originally posted by @Jefffrey in 
https://github.com/apache/arrow-rs/pull/6912#pullrequestreview-2561770071_
               


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