查询语句是由多条子查询拼接而成，单独执行里面的子查询速度很快，但整个sql执行时会很慢很慢，请大神帮助
select a.dbno_bi,a.names_bi,a.qsq,a.class2,a.incity,a.cwnames,months_tag
,a.Turnover
,a.Achievement
,a.Quantity_sold
,a.Transaction_nb,last_Turnover
,last_Quantity_sold,last_Transaction_nb
,Turnover_cost_amt
,last_Turnover_cost_amt
from
(
select dbno_bi,names_bi,qsq,class2,a.incity,dbno,closeif,a.cwnames
,sum(nb*endprice) Turnover
,sum(nb*c.rk_cost_price) Turnover_cost_amt
,null Achievement
,sum(nb) Quantity_sold
,count(distinct b.nos) Transaction_nb
from db_bi a
left join CMD..cmd_xjjx_sale b on a.dbno = b.store
and b.outdate >='20140407'
and b.outdate <='20140413'
and endprice <> 0
left join bi_product d
on d.colthno = b.colthno
and left(b.color,2) = d.color
and case d.classname1 when 'ANTHONY VACCARELLO' then 'STELLALUNA' when 'VIA SPIGA' then 'STELLALUNA' when 'PB Clothing' then 'PIERRE BALMAIN' else d.classname1 end in('STELLALUNA','PIERRE BALMAIN','WHATFOR','JKJY by STELLA')
left join bi_rk_cost c
on c.colthno = b.colthno
and left(b.color,2) = c.color
group by dbno_bi,names_bi,qsq,class2,incity,dbno,closeif,cwnames
) a
left join(
select dbno_bi,names_bi,qsq,class2,incity,a.cwnames
,sum(nb*endprice) last_Turnover
,null Achievement
,sum(nb) last_Quantity_sold
,sum(nb*c.rk_cost_price) last_Turnover_cost_amt
,count(distinct b.nos) last_Transaction_nb
from db_bi a
left join CMD..cmd_xjjx_sale b on a.dbno = b.store
and b.outdate >='20130408'
and b.outdate <='20130414'
and endprice <> 0
left join bi_product d
on d.colthno = b.colthno
and left(b.color,2) = d.color
and case d.classname1 when 'ANTHONY VACCARELLO' then 'STELLALUNA' when 'VIA SPIGA' then 'STELLALUNA' when 'PB Clothing' then 'PIERRE BALMAIN' else d.classname1 end in('STELLALUNA','PIERRE BALMAIN','WHATFOR','JKJY by STELLA')
left join bi_rk_cost c
on c.colthno = b.colthno
and left(b.color,2) = c.color
group by dbno_bi,names_bi,qsq,class2,incity,dbno,closeif,cwnames
)b
on a.dbno_bi = b.dbno_bi
and a.names_bi = b.names_bi
and a.class2 = b.class2
and a.incity = b.incity
left join
(
select sum(jmo) months_tag ,dbno
from zg_sales_des z
where
z.outdate >='20140407'
and z.outdate <='20140413'
group by dbno
)t
on a.dbno=t.dbno
where
a.class2 in('A')
and a.incity in ('East')
and a.names_bi not like '%已撤%'
and a.closeif='0'
order by Turnover desc
------解决方案--------------------
先把绿色的字右键，选择【缺少索引信息】，把那个索引建上去看看