收集统计信息让SQL走正确的执行计划

SELECT  a.dec_yt1 ,
        b.dec_yt1 ,
        a.dec_yt2 ,
        b.dec_yt2 ,
        a.dec_yt3 ,
        b.dec_yt3
FROM    ctlm8288 a ,
        ( SELECT    t.corr_id ,
                    t.clerk_id ,
                    ROUND(SUM(ISNULL(t.dec_yt1, 0)), 2) AS dec_yt1 ,
                    ROUND(SUM(ISNULL(t.dec_yt2, 0)), 2) AS dec_yt2 ,
                    ROUND(SUM(ISNULL(t.dec_yt3, 0)), 2) AS dec_yt3
          FROM      ( SELECT    b.corr_id ,
                                b.clerk_id ,
                                CASE WHEN d.feetype_flag = ‘1‘
                                     THEN ROUND(SUM(a.dec_sqty * c.fee_price),
                                                2)
                                END AS dec_yt1 ,
                                CASE WHEN d.feetype_flag = ‘2‘
                                     THEN ROUND(SUM(a.dec_sqty * c.fee_price),
                                                2)
                                END AS dec_yt2 ,
                                CASE WHEN d.feetype_flag = ‘3‘
                                     THEN ROUND(SUM(a.dec_sqty * c.fee_price),
                                                2)
                                END AS dec_yt3
                      FROM      ctlm8666 a ,
                                ctlm8001 b ,
                                v_saft04 c ,
                                ctlm8206 d
                      WHERE     a.terminal_id = b.terminal_id
                                AND b.dept_id = c.dept_id
                                AND a.item_id = c.vitem_id
                                AND c.fee_id = d.fee_id
                                AND d.flag_t = ‘Y‘
                                AND a.fiscal_year = 2015
                                AND a.fiscal_period <= 6
                                AND c.cur_year = 2015
                                AND b.tertype_id LIKE ‘0102%‘
                      GROUP BY  b.corr_id ,
                                b.clerk_id ,
                                c.fee_id ,
                                d.feetype_flag
                    ) t
          GROUP BY  t.corr_id ,
                    t.clerk_id
        ) b
WHERE   a.corr_id = b.corr_id
        AND a.clerk_id = b.clerk_id
        AND a.fiscal_year = 2015
        AND a.fiscal_period = 6

SELECT  COUNT(*)
FROM    ctlm8666 a
WHERE   a.fiscal_year = 2015
        AND a.fiscal_period <= 6--1650439
SELECT  COUNT(*)
FROM    ctlm8001 b
WHERE   b.tertype_id LIKE ‘0102%‘--229823