声明1:
create table tmp as select code , round((max(close)-min(close))/min(close),2) as volatility,
case when (max(close)-min(close))/min(close) <0.1 then "grade1"
when (max(close)-min(close))/min(close) <0.2 then "grade2"
when (max(close)-min(close))/min(close) <0.3 then "grade3"
else "grade4" end as type
from quote where date between '20120801' and '20121101' and code<'07000'
group by code order by volatility ;
声明2:
select tmp.code,profile.name, tmp.volatility from tmp,profile where tmp.code=profile.code;
语句1和语句2可以运行,当我将两者合二为一时-语句3无法运行,这是怎么回事?
声明 3:
select quote.code ,profile.name, round((max(quote.close)-min(quote.close))/min(quote.close),2) as quote.volatility,
case when (max(quote.close)-min(quote.close))/min(quote.close) <0.1 then "grade1"
when (max(quote.close)-min(quote.close))/min(quote.close) <0.2 then "grade2"
when (max(quote.close)-min(quote.close))/min(quote.close) <0.3 then "grade3"
else "grade4" end as quote.type
from quote,profile where quote.date between '20120801' and '20121101' and quote.code<'07000' and quote.code=profile.code
group by quote.code order by quote.volatility ;