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sqloraclesql-updatewindow-functions

SQL UPDATE in a SELECT rank over Partition sentence


There is my problem, I have a table like this:

Company, direction, type, year, month, value, rank

When I create the table, rank is 0 by default, and what I want is to update rank in the table using this select:

SELECT company, direction, type, year, month, value, rank() OVER (PARTITION BY direction, type, year, month ORDER BY value DESC) as rank
FROM table1
GROUP BY company, direction, type, year, month, value
ORDER BY company, direction, type, year, month, value;

This Select is working fine, but I can't find the way to use it to update table1

I have not find any answer solving a problem like this with this kind of sentence. If someone could give me any advice about if it is posible to do or not I would be very grateful.

Thanks!


Solution

  • You could join the sub-query and do an UPDATE:

    UPDATE table_name t2
    SET t2.rank=
      SELECT t1.rank FROM(
      SELECT company,
        direction,
        type,
        YEAR,
        MONTH,
        value,
        rank() OVER (PARTITION BY direction, type, YEAR, MONTH ORDER BY value DESC) AS rank
      FROM table_name
      GROUP BY company,
        direction,
        TYPE,
        YEAR,
        MONTH,
        VALUE
      ORDER BY company,
        direction,
        TYPE,
        YEAR,
        MONTH,
        VALUE
      ) t1
    WHERE t1.company = t2.company
    AND t1.direction = t2.direction;
    

    Add required conditions to the predicate.

    Or,

    You could use MERGE and keep that query in the USING clause:

    MERGE INTO table_name t USING
    (SELECT company,
      direction,
      TYPE,
      YEAR,
      MONTH,
      VALUE,
      rank() OVER (PARTITION BY direction, TYPE, YEAR, MONTH ORDER BY VALUE DESC) AS rank
    FROM table1
    GROUP BY company,
      direction,
      TYPE,
      YEAR,
      MONTH,
      VALUE
    ORDER BY company,
      direction,
      TYPE,
      YEAR,
      MONTH,
      VALUE
    ) s 
    ON(t.company = s.company AND t.direction = s.direction)
    WHEN MATCHED THEN
      UPDATE SET t.rank = s.rank;
    

    Add required conditions in the ON clause.