Oracle分组取第一条数据

对多数据进行分组排序后取每组第一条记录

Sql代码

SELECT *    

  FROM (SELECT ROW_NUMBER() OVER(PARTITION BY <PK_FINANCE_ACCOUNT_1> ORDER BY <amassdate> DESC) LEV,    

               <hx_amass_liquid>.*    

          FROM <hx_amass_liquid>)    

WHERE LEV = 1    

ORDER BY <PK_FINANCE_ACCOUNT_2> DESC  

SELECT * 

  FROM (SELECT ROW_NUMBER() OVER(PARTITION BY <PK_FINANCE_ACCOUNT_1> ORDER BY <amassdate> DESC) LEV, 

               <hx_amass_liquid>.* 

          FROM <hx_amass_liquid>) 

WHERE LEV = 1 

ORDER BY <PK_FINANCE_ACCOUNT_2> DESC

<PK_FINANCE_ACCOUNT_1> -- 分组列

<amassdate> -- 排序列

<hx_amass_liquid> -- 表名

<PK_FINANCE_ACCOUNT_2> -- 排序列

注：<hx_amass_liquid>.* -- 一定要有表名，否则会报“缺失表达式”错误

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分组时不仅想取每组的第一条记录，还想取每组共有几条记录

Sql代码

SELECT * 

FROM ( 

SELECT ROW_NUMBER() OVER(PARTITION BY PK_FINANCE_ACCOUNT ORDER BY amassdate DESC) LEV, 

              

             count(0) over(partition by PK_FINANCE_ACCOUNT) cnt, 

              

             hx_amass_liquid.* 

FROM  

hx_amass_liquid 

) 

WHERE LEV = 1 

ORDER BY PK_FINANCE_ACCOUNT DESC