2019獨角獸企業重金招聘Python工程師標準>>>
第一步:創建表及數據:
create table uid(uid int, --uidcate varchar(20), --類別price double --金額
)
insert into uid values(123,'c1',21);
insert into uid values(123,'c2',23);
insert into uid values(123,'c3',14);
insert into uid values(123,'c4',25);
insert into uid values(123,'c8',10);
insert into uid values(124,'c1',28);
insert into uid values(124,'c15',25);
insert into uid values(124,'c2',12);
insert into uid values(124,'c31',40);
insert into uid values(124,'c7',15);
查詢結果:
第二步:取uid的金額最多的前四名
1.獲取所有記錄
2.增加序列并過濾(增加序列需要排序):
4.完成并查詢結果:
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