(select subsid,
acctid,
custid,
row_number() over(partition by servnumber order by createdate desc) rn
from rec_subscriber
where servnumber = v_servnumber)
where rn = 1;
row_number() over(partition by servnumber order by createdate desc) rn --这句话看不懂是什么意思,麻烦各位大哥解释下,越详细越好
acctid,
custid,
row_number() over(partition by servnumber order by createdate desc) rn
from rec_subscriber
where servnumber = v_servnumber)
where rn = 1;
row_number() over(partition by servnumber order by createdate desc) rn --这句话看不懂是什么意思,麻烦各位大哥解释下,越详细越好
你google下就明白了
row_number()是函数名,后面的over(partition by servnumber--按servnumber分组
order by createdate desc)--按createdate从大到小
按照over后面的规则对记录赋以序号
而且很容易搜到更详细更容易懂的回答
partition by是这个函数的可选参数,order by 是必须的,否则就没有排序的规则
rn是列别名,随便你取
有办法的话自己测试一下,记忆更深刻