根据 SQL 上的其他常见列将行与空列合并

Question

我是运行仪表盘工具的 SQL 查询，该工具给出 table 结果如下：

article_name   color    spec1   spec2
article1       brown     0 
article2       blue      1       
article2       blue              3

我的查询：

select a.name as article_name
       c.clr as color
       d.sp  as spec1
       k.sps as spec2
from table_a a 
left join table_c c on a.id=c.id
left join table_d d on a.id=d.id
left join table_k k on a.id=k.id;

我想编辑该查询以获得如下结果：

article_name   color    spec1   spec2
article1       brown     0 
article2       blue      1       3

关于如何达到该结果的任何想法？

Answer 1

显然未经测试，但请尝试对 spec1/2 列进行分组和聚合：

select a.name as article_name
       c.clr as color
       max(d.sp)  as spec1
       max(k.sps) as spec2
from table_a a 
left join table_c c on a.id=c.id
left join table_d d on a.id=d.id
left join table_k k on a.id=k.id
group by a.name, c.clr;

根据 SQL 上的其他常见列将行与空列合并

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