Oracle分组取第一条数据
对Oracle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