performance - クエリの最適化/パフォーマンス

Question

パフォーマンスの悪い SQL クエリがあります。テーブル スキャンや IO スパイクが発生しています。以下のスクリプトと実行計画を確認し、クエリ自体のインデックスまたはリファクタリングが必要かどうかをお知らせください。ありがとう

--クエリ

SELECT TOP 20
        CustomerPrimaryExtID,
        Max(POSTimeStamp) AS TransactionDate,
        ExtLocationCode,
        0 AS RedemptionAmount,
        0 AS RedemptionCount,
        TerminalNum,
        LogixTransNum,
        POSTransNum AS TransNum,
        0 AS DetailRecords,
        CustomerTypeID,
        PresentedCustomerID,
        PresentedCardTypeID,
        HHID,
        Replayed,
        0 AS TransContext,
        ISNULL(TransTotal, 0) AS TransTotal
    FROM TransHist AS TH WITH(nolock)
    WHERE 
        ( 
            ( 
                ( CustomerPrimaryExtID IN ( '' ) AND HHID IS NULL )
                OR HHID = '0000000250000007320' AND CustomerTypeID <> 1 
            )   OR ( CustomerPrimaryExtID = '0000000250000007320'   AND CustomerTypeID = 1 )
        )
        AND NOT EXISTS
        (
            SELECT
                    LogixTransNum
                FROM   TransRedemptionView AS TR2
                WHERE  
                    (
                        ( ( CustomerPrimaryExtID IN ( '' )  AND HHID IS NULL )  OR HHID = '0000000250000007320' AND CustomerTypeID <> 1 )
                        OR ( CustomerPrimaryExtID = '0000000250000007320'   AND CustomerTypeID = 1 )
                    )
                    AND TH.LogixTransNum = TR2.LogixTransNum
        )
    GROUP  BY
        CustomerPrimaryExtID,
        HHID,
        CustomerTypeID,
        PresentedCustomerID,
        PresentedCardTypeID,
        LogixTransNum,
        POSTransNum,
        TerminalNum,
        ExtLocationCode,
        Replayed,
        TransTotal
    ORDER  BY TransactionDate DESC