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Window functions in an update statement in Oracle SQL


I am using Oracle SQL DB 19c. Tried the following Oracle SQL scripts but none of them worked to add a column to my table with window expression.

The first script runs to an error message: "SQL command not properly ended":

UPDATE TRANSACTION_HISTORY SET TRANSACTION_HISTORY.ID = X.RN
    FROM
    (SELECT SEQUENCE,
    ROW_NUMBER() OVER (PARTITION BY TRANSACTION_DATE, TRANSACTION_PARTNER ORDER BY TRANSACTION_DATE, TRANSACTION_PARTNER ASC) AS RN
    FROM TRANSACTION_HISTORY
    ) AS X
    WHERE TRANSACTION_HISTORY.SEQUENCE = X.SEQUENCE

The second one runs to an error message: "missing ON keyword" but ON is there:

merge into TH USING
    (SELECT TRANSACTION_DATE, TRANSACTION_PARTNER, SEQUENCE,
    ROW_NUMBER() OVER (PARTITION BY TRANSACTION_DATE, TRANSACTION_PARTNER ORDER BY TRANSACTION_DATE, TRANSACTION_PARTNER ASC) AS RN
    FROM TRANSACTION_HISTORY TH
    ) X
ON X.SEQUENCE = TH.SEQUENCE
WHEN MATCHED THEN UPDATE 
SET TH.ID = X.RN

Can someone please help?


Solution

  • You need parenthesis after ON as follows:

    merge into TH USING
        (SELECT SEQUENCE, 
                ROW_NUMBER() OVER (PARTITION BY TRANSACTION_DATE, TRANSACTION_PARTNER 
                                  ORDER BY TRANSACTION_DATE, TRANSACTION_PARTNER ASC) AS RN
        FROM TRANSACTION_HISTORY TH
        ) X
    ON (X.SEQUENCE = TH.SEQUENCE) -- you need to use parenthesis
    WHEN MATCHED THEN UPDATE 
    SET TH.ID = X.RN