将SELECT（NOLOCK，READUNCOMMITTED）放在select语句的更新块中是否正确？

 UPDATE
        BondPrices
    SET
        MarketValueOwned = Holdings.Amount
    FROM
        BondPrices BondPrices
        INNER JOIN
        (
            SELECT
                PM.SecurityId,
                SUM(Pos.QuantityTraded * Pos.Mark) AS Amount
            FROM
                Position Pos --WITH (NOLOCK, READUNCOMMITTED)
                INNER JOIN
                PositionMaster PM --WITH (NOLOCK, READUNCOMMITTED)
                       ON
                    Pos.PositionMasterId = PM.PositionMasterId
            WHERE
                Pos.Date = @ReportDate 
            GROUP BY
                PM.SecurityId
        ) Holdings ON
            BondPrices.SecurityId = Holdings.SecurityId
    WHERE
        BondPrices.Date = @ReportDate  
 UPDATE
        BondPrices
    SET
        Mark