select s_info_windcode from asharettmandmrq where
report_period between 20170506 and 20180525 order by report_period asc
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提取最新的流通股數(shù)
先選出wind代碼恶守、流通股第献、變動(dòng)日期 按照wind代碼分類，將變動(dòng)日期排序兔港，從高到低庸毫，并編號(hào)
再選出wind代碼、流通股股數(shù)衫樊，從n=1里面提取飒赃，也就是最新的那期
select s_info_windcode, float_shr * 10000 as float_shr from
(select s_info_windcode,float_shr,change_dt, row_number() over(partition by s_info_windcode order by change_dt desc) as n from asharecapitalization) where n = 1
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解釋部分
row_number() over()
將分?jǐn)?shù)從大到小排列，并將其排名
select [name],gender,fenshu, row_number() over(order by fenshu desc) as num from dbo.PeopleInfo
將男女分別算科侈，還是將分?jǐn)?shù)排名并排名次
select [name],gender,fenshu, row_number() over(partition by Gender order by fenshu desc) as num from dbo.PeopleInfo
matlab中插入臨時(shí)表
fastinsert(conn,'temp_windcode',{'stockcode'},StockCode);
創(chuàng)建臨時(shí)表载佳，復(fù)制temp_windcode的結(jié)構(gòu)，不復(fù)制數(shù)據(jù)
create table temp_windcode_xia as select * from temp_windcode where 1=0;
