不是在max中选择的单组分组功能 [英] not a single-group group function with MAX in select

问题描述

Select sg_gameno, Max(sg_Year), sg_end, sg_hostcity, country_olympic_name
  from Summergames s, Country co
 where s.country_isocode = co.country_isocode 

不知道这有什么问题.我想获得最近的一年.我应该使用MAX还是其他?

Don't know whats wrong with this. I want to get the lastest year. Should i use MAX or something else.

推荐答案

如果要聚合一个列(sg_year)，而不要聚合其他列，则需要GROUP BY子句.

If you want to aggregate one column (sg_year) and to not aggregate others, you need a GROUP BY clause.

Select sg_gameno, Max(sg_Year), sg_end, sg_hostcity, country_olympic_name
  from Summergames s, 
       Country co
 where s.country_isocode = co.country_isocode 
 group by sg_gameno, sg_end, sg_hostcity, country_olympic_name

在语法上有效.是否为您提供所需的结果是另一个问题-您需要告诉我们表的外观，表中的数据，所需的结果等.

is syntactically valid. Whether it provides you the results you want is another question-- you'd need to tell us what your tables look like, what data is in them, what result you want, etc.

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