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  • 使用distinct消除重复记录的同时又能选取多个字段值

    需求是:我要消除name字段值重复的记录,同时又要得到id字段的值,其中id是自增字段。 
    select distinct name from t1 能消除重复记录,但只能取一个字段,现在要同时取id,name这2个字段的值。 
    select distinct id,name from t1 可以取多个字段,但只能消除这2个字段值全部相同的记录 
    最后解决方法: 

    SELECT id,name FROM t1 WHERE id IN(SELECT MAX(id) FROM t1 GROUP BY name) order by id desc
    select distinct parameter_power_max, parameter_id from charge_parameter;

    select * from charge_parameter
    where parameter_id in (select max(parameter_id) from charge_parameter group by parameter_power_max) order by parameter_id;

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  • 原文地址:https://www.cnblogs.com/bulrush/p/10501510.html
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