如图,我有 这样一份数据
字段比较多,大约有30个多字段.我想根据宝贝id 和 日期进行去重处理. 简单的说就是2列去重我查了一下distinct方法是去重的但是我执行了如下语句SELECT distinct 宝贝id FROM taobao.jutiliushi;
distinct
SELECT distinct 宝贝id FROM taobao.jutiliushi;
恩所有的字段都没了~,我不知道网上找到这种去重的方法有什么意义~
所以想问下,假如我想针对多个字段去重,同时又能保持表的结构?怎么处理?
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What you need isgroup by
group by
select * from taobao.jutiliushi group by 宝贝id;
select distinct id, date,....column name from table name
SELECT DISTINCT(baby id) AS id, date, baby title,... FROM table name;
You only selected the baby id, and of course the result will only be the baby id
SELECT * FROM (SELECT * FROM `表A` GROUP BY 去重字段1) as aa GROUP BY aa.去重字段2
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What you need is
group byselect distinct id, date,....column name from table name
SELECT DISTINCT(baby id) AS id, date, baby title,... FROM table name;
You only selected the baby id, and of course the result will only be the baby id